Blended with the Savior: Gregory of Nyssa's Eucharistic Pharmacology in the Catechetical Oration

In the wake of the “material turn” in Late Antiquity, what new histories might be possible if we took seriously the unruly potencies ancient Christians attributed to the drugs they prescribed and digested? Within the material turn there is need for a corollary and equally significant pharmacological turn—a recognition that the temporary congealment of materiality called the human body was, for many early Christian authors, capable of being augmented, developed, and even divinized through the strategic and ritual use of medical substances. We might call this a Christian materia medica.

Drug histories provide us with an important narrative frame for understanding how certain substances shaped bodies, social relations, and cultures. One prime example of how drug history and early Christian history coalesce is found in the writings of fourth-century Cappadocian bishop Gregory of Nyssa (c. 335–394). In his Catechetical Oration, Gregory engages in an elaborate discussion of human physiology in order to explain the power and purpose of the Eucharistic bread. In one passage, his argument seems to reach a rather straightforward and spiritual conclusion: in the ritual act of eating bread the human body is healed of some deadly poison and, in so doing, the participants initiate a process of becoming that culminates in union with God in body as much as soul. He explains: “But it is in a different way that the body becomes united and is blended with its Savior. Those who have been tricked into taking poison offset its harmful effect by another drug.”³ Yet this brief observation about the medicinal effect of eating the Eucharistic bread raises questions about Gregory's understanding of the ritual. Is Gregory's pharmacological reasoning merely a rhetorical strategy in the unfolding of a catechetical program? Or does it reflect a deeper commitment to the practical function of medicine in Christian ritual?

For some time, scholars have puzzled over the Catechetical Oration, fixated primarily upon Gregory's reference to the idea of apokatastasis (or final restoration of all things in God at the end of time).⁴ Far less attention has been paid to his discussion of the Eucharistic ritual as a kind of medical event. Indeed, even those scholars who have noted the medical logic operative within the Oration have quickly dismissed its significance. For example, Edward Hardy saw in it more rhetorical flourish than sophisticated medical speculation: “Gregory's style is that of a rhetorician. The sentences are frequently long, and at times digressions and parentheses interrupt the flow of the argument. Synonyms and similes abound. A number of the latter are taken from medicine, and many of them are elaborated unduly.”⁵ Another editor of the Oration, taking a different tack, concluded that Gregory's “one-sided treatment has the effect of seeming to lower the Eucharistic gift to a mere principle of life for the body.”⁶ The first interpreter sees Gregory's use of medicine, physiology, and pharmacology as a needlessly complex analogy. The second sees an embarrassing strand of physicalism in the Cappadocian's liturgical theology.

Even more recent scholarship has stumbled over the function of medicine in this literature by minimizing its actual impact. Gary Ferngren, for example, has observed that the “theme of ‘Christus medicus’ is a familiar one, appearing very early….One finds it employed through the second century, and it quickly becomes commonplace. It is primarily in its metaphorical sense, and rarely in its literal meaning, that Christian writers describe Jesus as the healer of humankind.”⁷ And so Ferngren concludes that, “we find in [the Apostolic Fathers] no specific mention of contemporary healing practices”⁸ and that the evidence from early Christianity in general “overwhelmingly indicates that Christianity did not promise physical healing.”⁹ From these examples, then, the reader is left with the choice of either dismissing Gregory's account of the Eucharist as an over-wrought metaphor ancillary to a deeper, spiritual reality or as a reductive and unspiritual materialism of the gut that detracts from Gregory's overall catechetical project. Both options strike me as dead-ends that fail to capture the full force of how medicine, dietetics, and pharmacology function in texts such as Gregory's Oration. I stand with a small but growing group of scholars who argue that there is more at work in the medical matter found in early Christian literature.¹⁰ 

One factor contributing to older scholarly approaches, I think, is a tendency to use tidy modern categories for ancient Christian medical reasoning, relegating the health of the body and the health of the soul to two separate spheres of knowledge that require two separate, if analogically similar, modes of care. Medical references in early Christian discourse are thereby categorized either as mere metaphor, and so unconcerned with the body, or directed toward “real” healing, and so not concerned with the soul. Heidi Marx has recently called this approach into question, emphasizing instead the “transdisciplinary” nature of ancient medical knowledge.¹¹ She suggests that, while medical writers “may at times identify distinctions between medical and philosophical modes of thinking, [they] do not in practice observe or enforce such boundaries.”¹² 

In this way, Marx builds upon an intervention previously put forth by Michel Foucault in The Care of the Self, the third volume in The History of Sexuality trilogy. There, Foucault explores how this relationship between medicine and metaphor provided authors in Greco-Roman antiquity a potent register in which to discuss the soul's relationship to the body:

The analogizing of health care and soul care was prompted, in part, by the notion that the afflictions could traverse the physical and the spiritual. Symptoms were potent symbols indicating the malleability of human nature and the powerful ways in which disease could insinuate itself across that nature.

This helps explain the medicalizing of Christian thought and practice from the earliest literature of the tradition. The burgeoning of medical knowledge as an institution, for Foucault, was related to the rise of spiritual direction and pastoral care.¹⁴ The office of the pastor, often likened to that of a physician in antiquity, entailed highly specific strategies that were informed by and mimicked medical methods of knowing and treating the body. These strategies offered “a way of living, a reflective mode of relation to oneself, to one's body, to food, to wakefulness and sleep, to the various activities and to the environment. Medicine was expected to propose, in the form of regimen, a voluntary and rational structure of conduct.”¹⁵ Which is to say, the regimens of bodily care and the regimens of soul care were not easily distinguishable forms of therapy, the former pursued by physicians and the latter by clerics. Indeed, medical and religious practitioners shared in the belief that dietetics and other strategies concerning nutrition, digestion, and pharmacology could be leveraged for the benefit of body and soul alike.

This intertwining of the mental and the physical, the metaphoric and literal, is evident across the work of Gregory of Nyssa. In On Virginity 23, for instance, Gregory describes philosophy as “the healing art of the soul” (τῆς τῶν ψυχῶν ἰατρικῆς), comparing it to the art of medicine in which physicians learn how best to treat physical ailments.¹⁶ Here, the diagnostic methodology is identical, but the diseases and their locations appear to be distinct. Yet, in the previous section of On Virginity, this distinction folds in on itself. In chapter 22, Gregory explicitly refers to the ancient understanding of the body's mixtures—a medical method he says he learned from “a certain physician”—in order to demonstrate that close attention to diet is crucial for the soul's proper balance and pursuit of perfection.¹⁷ My contention is that, in analogical moments like this, Gregory does not reflect a strict partitioning of bodily and spiritual healing, but rather relies on the pervasive understanding within medical reasoning that the health and disease of body and soul were intimately interconnected. Moreover, passages like this reveal Gregory's tendency to return regularly to the crucial insight that the potency of ingestible matter can be leveraged to heal and transform and even bring to perfection the sickly souls of human creatures.

From this premise, I want to reconsider the ritual of Eucharistic eating as a medical regimen of dietetics—a mode of gastronomic therapy premised on the belief that health care was, in fact, a form of soul care, and that the transformation of the physical body into a spiritual one required the ingestion of an edible matter imbued with spiritual power.¹⁸ Following Foucault, I want to take seriously the medical methodologies, knowledges, and practices embedded within Gregory of Nyssa's approach to the Eucharistic bread. I am proposing a more robust materialist framework in which to analyze the healing effects Gregory ascribes to the Eucharist—an approach that places in tension the spiritual or theological meaning ascribed to the ritual with the highly theorized physiological processes upon which the efficacy of the ritual depended. Such an approach seeks not to prioritize the literal over the metaphoric when it comes to the medical reasoning Gregory uses to describe this ritualized eating. Rather I aim to show how, for many ancient authors including Gregory, interest in the pharmacological effects of ritual substances indicates an important point of slippage between metaphoric and literal medical language. The Eucharistic bread, in this way, becomes a ritualized remedy with the goal of healing and transforming the whole of human nature.

Texts such as Gregory's On Virginity and the Catechetical Oration draw deeply on medical concepts, vocabulary, and methods of treatment not simply because they were “good to think with,” but more emphatically because medicine was a comprehensive system in which to speak of the human condition and to understand the care (physical, spiritual, whatever) required for the well-being of embodied souls. In the case of the ritual system of the Catechetical Oration, this medical reasoning takes on greater practical urgency. That is, when linked to medical knowledge, the ritual consumption of bread enacts this comprehensive system, plotting the initiate within a journey from the precipice of sickness, sin, and death to the flourishing of health, salvation, and life.

My argument here hinges not simply on pharmacological effects attributed to bread, but more specifically on the crucial concept of “mixture” or “blending”—referred to as krasis in Greek discourse about the body.¹⁹ This is what Gregory refers to in passing in On Virginity and develops at length in his Catechetical Oration. In the first section of this paper, I explore how this concept appears regularly in philosophical and medical treatises as an explanation for the proper ordering of the material, sensible world. But mixture was also crucial (most notably in Galen) in assessing and treating the psychosomatic health of the human person. Within these ancient theories about the body's balance, food functioned as a potent resource that could sustain or debilitate the health of body and soul. This is because food was thought to contain its own unique mixture (a particular balance of hot, cold, wet, and dry) that could impact the internal balance of the one eating it. With an understanding of krasis as a cosmology, a condition of material existence, and as a dietetic therapy for achieving individual well-being, we turn in the second section of the paper to how this broader medical epistemology underwrites Gregory's thinking throughout the Oration. Finally, as I argue in section three, it is in relation to this concept of krasis that we must situate Gregory's discussion of the Eucharistic bread as a healing drug in section 37 of the Oration: not, as some scholars have suggested, as an overwrought and ultimately disposable medical analogy at the service of a more important theological or spiritual truth, but rather as an edible means for the working out of God's salvation and the first, physical ingestion of that final, eschatological blending of all things into the life of God.

In his treatise Parts of Animals, Aristotle observes: “It is perhaps obvious that these four principles are the causes of life and death…sickness and health.”²⁰ He is referring to heat (θερμός), cold (ψυχρός), wet (ὑγρόν), and dry (ξηρός). These four principles or qualities were often found in close proximity to ancient medical and philosophical speculation about the four elements (fire, air, water, earth) and the four humors (yellow bile, blood, phlegm, black bile). Cosmic matter, ethnic groups, individuals, non-human animals, geographical regions, seasons of the year, drugs, as well as food and drink were thought to contain a unique combination of these four qualities. Indeed, the qualities were so pervasive in ancient theories of material reality that they are often referred to simply as a “mixture,” “blending,” or “temperament” (κρᾶσις in Greek, temperamentum in Latin). As we will see, it is this concept of mixture that structures Gregory's physiological and medical reflections on the efficacy of Eucharistic bread.

Mixture appears widely in Hippocratic treatises as a method for thinking about an individual's health and the conditions that impinge upon it.²¹ In Airs, Waters, Places, traveling physicians who have recently arrived in a new town are urged to survey the conditions of the region—its climate and habitability—prior to seeing any patients. The doctor is, in this text, a part-time ethnographer who must make deductions about the character and physiology of a people based on the effects of their surroundings.²² Geographical survey helps the physician to correlate the mixtures produced by a particular environment with the inhabitants’ internal (im)balance of the humoral compositions. In this way, the mixtures of a region's climate help to explain, at least in part, the mixtures of individual humans in that region and the unique expression of health or illness endemic to them.²³ 

Although assuming a two- (rather than four-) element model for the material world, the Hippocratic author of Regimen likewise employs a view of the human and cosmos as bound together by parallel structures, what Jacques Jouanna has referred to as a “cosmological anthropology.”^24,Regimen describes how “all animals, including humans, are composed of two things, different in power but working together in their use, namely, fire and water.”²⁵ These two fundamental elements contain the four qualities (fire containing hot and dry, water containing cold and wet). The human person, then, is a microcosm of this interaction between fire and water that takes place in all material things throughout the cosmos. The soul, too, is a product of such a mixture: “Into the human person there enters a soul, a blend of fire and water, a portion of a human body. These…are nourished and increased by human diet.”²⁶ And so ancient medical wisdom about the material composition of the body and the blending of its constitutive elements readily engaged in philosophical speculation about the relationship between cosmology and anthropology.

In the Timaeus, medical knowledge provides a robust grammar for describing the cosmological contingencies of being an embodied soul.²⁷ For Plato, the four elements and their attendant qualities structure the human body in the same way as the body of the cosmos, what Aristotle later calls the fundamental “principles of the physical elements” (ἀρχαὶ τῶν φυσικῶν στοιχείων).²⁸ Cosmology and anthropology mirror one another because all bodies contain a unique mixture of these physical elements: the stoicheia (στοιχεῖα).²⁹ Disease, in this framework, is an imbalanced mixture of hot, cold, wet, dry in a given body.³⁰ But the Timaeus pushes this point even further, observing that a “sickness of the soul” (νόσος ψυχῆς), often due to excessive wetness, is therefore symptomatic of these fluctuating essences within the body:

The sick body and the sick soul communicate to one another by means of the elemental mixtures which bind them together. When left unchecked, the humors build up in certain portions of the body causing an imbalance of hot, cold, wetness, and dryness. These, in turn, are blended with the soul and transmit sickness to the higher rational functioning of the intellect. The verb for “blend” used here is anakerannumi (ἀνακεράννῡμι), a cognate of our central theme krasis (κρᾶσις). As Vivian Nutton has explained, the “physicalist strain” within Plato's approach to disease requires that sicknesses of mind and soul involve “treatment of the underlying physical condition.”³² Mixture, then, is not only a crucial component linking the structure of cosmic bodies to that of human bodies. It also represents a mode of understanding the sicknesses that afflict body and soul alike, offering an etiological system for diagnosing and treating disease.

Drawing upon aspects of all these traditions, Galen too presents the mixtures of the body as a holistic explanation for the human condition and its ailments.³³ His medical system at times de-emphasizes the humors in order to accentuate the four principle qualities as the primary factor determining health.³⁴ Each individual contains a distinct mixture of hot, cold, wet, and dry. The skilled physician, according to Galen, must begin with their patients’ unique mixture as the primary site at which to diagnose disease and the primary indicator of treatments required. The importance of mixture in Galenic thought is evident in the use of the term throughout his corpus: the root word krasis appears pervasively, some 1,500 hits on the TLG before even searching for cognates, and it is even used as the title for one important work.³⁵ Health is often described as a well-balanced, or eukratic, state (εὐκρασία) while disease is equated with an imbalanced, or dyskratic, state (δυσκρασία). Galen's system so hinges on krasis that, according to one scholar, it seems to provide “a full causal explanation for everything in the human body,” including even the character and health of one's soul.³⁶ 

In his treatise On Mixtures, Galen explicitly develops this connection between physiological mixture and moral quality, observing specific combinations of the four qualities to a particular character of the soul (ψυχῆς ἦθος): “If the individual is cold and dry from the start, the constitution of this individual's body is white, soft, hairless, without visible vessels and joints, slim and cold to the touch; and the character of his soul is retiring, cowardly, and depressed; yet his residues are not melancholic.”³⁷ Galen's primary concern here is on the residues (perritomata/περιττώματα) produced by the humors, which are symptomatic of the particular proportion of hot, cold, wet, and dry found in the body. According to Galen, residues are naturally occurring in human physiology. But the proper balance of the body's krasis—and so the achievement and maintenance of good health—depends upon the regular “hustle and flow” of the body's material excess out of its system. Left unattended, these residues become dangerous congealments, inevitably leading to disease and even death. Medical treatment must be aimed first and foremost at maintaining the balance of these principle qualities in order to prevent harmful residue buildup.

Mixture and moral character are drawn even closer together when Galen prescribes treatments using food, drink, and drugs in order to address dyskratic states of the body. In The Capacities of the Soul Depend on the Mixtures of the Body, Galen argues that “we bring about good mixture in the body through what we eat and drink, and also through our daily practices, and from this good mixture (εὐκρασία) we will produce virtue in the soul.”³⁸ Strategic modification of the mixtures, then, is not simply a first step toward bodily health but also a crucial foundation for the health of the soul and a person's subsequent cultivation of virtue. Toward the end of the treatise, Galen concludes that a proper diet will enable a person to “make progress in the capacities of their rational souls, becoming more intelligent in virtue and increasing their power of memory.” He encourages anyone interested to take his advice not only on the “winds, mixtures of the ambient air, and even about which countries are to be chosen and which avoided” but also, more specifically, which types of food and drink will be most beneficial as a dietetic therapy for body and soul alike.³⁹ 

For Galen, the path to a healthy body and a healthy soul begins in the stomach. It is there that effective remedies must first be directed. Through the stomach, food's healing power accesses the whole system of the body, eventually working its way into the soul. Specifically, Galen urges doctors to consider “the condition of the [patient's] stomach” prior to seeking a suitable remedy.⁴⁰ If the stomach is cold, heat it up. If moist, dry it. If some unhealthy combination, treat it with the opposite combination. Such modifications of the patient's condition are achieved through the use of food and drug, both of which effected changes in the mixture of the body. As a result of this regimented ingestion aimed at balancing the imbalanced patient, the line between what constitutes food and what constitutes drug is intentionally blurred.⁴¹ Different foods contain different potencies. Digestion, for Galen, converts the unique potency of edible matter into a technology for fine-tuning the body's inner system.⁴² Drugs and drug-like foods enact other combinations of the principle qualities when applied to the body or consumed within it. And so foods and drugs provide the physician a range of potencies with which to modulate and calibrate the qualities that impinge upon the health of body and soul. And this constant modulation of hot, cold, wet, and dry through dietary and pharmacological intervention is the best strategy for achieving Galen's eukratic ideal.

This sprawling and complex set of concerns surrounding the concept of krasis in ancient medicine should prompt a more thorough reconsideration of its function in early Christian authors such as Gregory of Nyssa. Scholars have tended to focus upon the fraught legacy of “mixture” in later Christological debates, often noting its resonance in Aristotelian or Stoic philosophy with less attention to the ways in which these relate to ancient medical knowledge.⁴³ Although ideas like “blending,” “commingling,” and “mixture” became troublesome in later doctrinal disputes, krasis was at the very heart of how Gregory understood the human condition as well as the power of Eucharistic bread to address the intractable infirmities of that condition.⁴⁴ Even among Gregory's closest conversation partners—his brother Basil and Gregory of Nazianzus—both medicine in general and krasis in particular provide structuring logic to their ascetic, pastoral, and theological programs.⁴⁵ 

Indeed, in his Homilies on the Lord's Prayer, Gregory is so committed to this epistemological orientation that he refers to krasis as the “law of medicine.”⁴⁶ Analyzing the mechanics of Gregory's commitment to the “law of medicine” helps us better understand his consistent use of the terminology in doctrinal speculation—as, for example, in his anti-Apollinarian writings where he suggests that, “God…mixed himself with human nature in order to destroy sin….It is as in medicine.”⁴⁷ But it also forces us to pay closer attention to how this notion of medicine and mixture functions in his speculation on Eucharistic ritual as well. My contention, then, is that we must retain the force of krasis in its full medico-philosophical framework in order to better situate the structuring role of medical reasoning in Gregory's writing. Reframing his appeal to krasis in its particular pre-Chalcedonian moment, not tinged (at least as much as possible) by the post-Chalcedonian arguments that would color its use in later polemic, enables us to see the dynamic relationship between medical knowledge and theological speculation without immediately assuming that the latter always guides the former.

In the context of the Catechetical Oration, Gregory's thoroughgoing use of krasis—whether at the service of a general theological anthropology or a specific account of Eucharistic efficacy—indicates the suffusing reach of medical reasoning within his program for the formation of new Christians. As we have seen, in Hippocratic, Platonic, and Galenic formulations of human health and physiology, krasis was a system of knowledge through which other systems of knowing the human person were refracted. Gregory draws on krasis (on the role of mixture in the environment, in the human constitution, in dietetics and drugs) in order to diagnose the dyskrasia of the human person resulting from Eden's poison and to prescribe the Eucharist as an antidote with the power to induce a divine eukrasia.

Mixture is fundamental to Gregory's anthropological system, enabling an account of humans’ capacity for transformation. Gregory presents human nature as a fleshy-spiritual congealment of becoming. Human nature is plastic, porous, liable to shaping and reshaping. This malleability necessarily involves the risk of imbalance, but it also allows for healing matter to be delivered from the outermost parts to the innermost. Nutrition and dietetics are, in this way, critical modes of medical intervention and ground Gregory's notion of the salvific role of eating.

The anthropological framework Gregory develops in the Catechetical Oration is similar to his consideration of the human person “from a medical point of view” found in On the Making of Man where he observes:

To sustain life, the human body requires balance and balance requires constant care. The four qualities that structure human life are not sustainable internally, and so food and drink must be regularly consumed to preserve that life and help it to flourish. The proper ordering of the human person, even in the sight of God, necessitates regular medical intervention and treatment. Gregory's program of catechesis found in the Catechetical Oration—his outline for the formation of embodied souls—is not merely a blueprint of spiritual direction for the newly initiated. It is also a diagnostic regimen: illnesses must be identified, the body's diseased viscera probed, and remedies prescribed. Gregory's catechetical program addresses the initiate as a sick person on the precipice of a great change, whether into deeper disrepair if the program is ignored or, if followed, into the promised health of salvation. Union with God requires, first and foremost, the healing regimen of medical care—a re-balancing of vital mixtures currently thrown off-kilter.

The medical framework of this text is flagged from the outset when, in the prologue, Gregory contends that “the method of healing must be adapted to the form of the sickness.”⁴⁹ To be sure, by “form of the sickness” Gregory is identifying errant teachings, like those of Marcion and Valentinus, but this diagnosis also situates the fundamental relationship between proper doctrinal formation and physical well-being—the nexus of religious belief and medical physiology that is articulated throughout the Oration. Humanity was created to participate in divine goodness, he says a little later, and so human nature had to be constructed in such a way that it could contain that goodness. The image of God is located deep inside each person, a place where divinity and humanity are blended together (ἐγκεράννυμι, a cognate of κρᾶσις).⁵⁰ 

But something went wrong. This balanced mixture of human nature and divine goodness did not hold. Death entered into the system, dissolving life's structuring elements in the process. In an early section, Gregory describes death's entry as the result of an act of poisoning, linking it to his insistence that the fruit of Eden poisoned humanity in perpetuity. He diagnoses the sickness: humanity swallowed death in a honey-sweetened drug (δηλητήριον μέλιτι) and so mingled (καταμείγνυμι) evil into that sentient part of our nature.⁵¹ By this venom, mortality took root within the human frame, clothing it with death, and dissolving the cosmic elements within humanity that are meant for harmonious mixture.⁵² It is through the senses that the sickness of sin gained entry, separating life from body and goodness from the soul. Both body and soul, then, are wounded, imbalanced—each having been made ill by the toxin of evil.⁵³ 

Gregory next describes the different ways in which the soul and the body are affected by the poison. He observes a “bond and fellowship” between body and soul, noting the wounds each undergo at the hands of sinful passions. Both require medical treatment: the soul with the medicine of virtue and the body with other therapies. The primary concern for Gregory is that the soul, like the body, is sick even though it cannot be dissolved and destroyed like the elements of the body. Nevertheless, there are a range of symptoms (παθήματα) that reveal the brokenness of both body and soul. Sickness impinges upon the composite creature's twofold nature, and so its symptoms are found everywhere.

In the same section of the Oration, Gregory clearly pushes the language beyond the limits of metaphor as he diagnoses the sin-induced illness of the soul. The disease of sin, he observes, results in “material excrescences that have hardened upon the surface of the soul, which itself has become fleshy through association with the passions.”⁵⁴ Drawing upon the Pauline distinction of spiritual and fleshy, Gregory in fact suggests here that the distinction between soul and body breaks down in the case of those untreated people still suffering Eden's poison and its myriad symptoms: their soul becomes fleshy (ἀποσαρκόομαι) when mired in the passions, resulting in cancerous growths upon its surface (ὑλώδη περιττώματα ἐπιπωροῦται). Now pocked by lumps, the soul requires medical intervention.

Gregory uses the term perittoma (περίττωμα) to describe the harmful build-up that turns the soul to flesh. As we have seen in the ancient medical traditions explored earlier, perittoma referred to the residue left by partially digested food and drink that could result in humoral imbalance.⁵⁵ This excess of residue was thought to instigate bad mixture within the body. When not treated properly and flushed from the body, residues leach toxin into the system leading to pain, disease, and death. In using this term, Gregory collapses his distinction between sicknesses of body and soul when he suggests that the soul, through sin, grows deadly lumps of flesh due to the untreated poison of Eden. For Gregory, as for Galen and other medical writers, the essences churning inside the body directly impact the psychosomatic balance of a person's nature. The relationship between bodies and souls, then, is one of diagnostic and not simply analogic significance. The theory of preventive medicine described here requires that one monitor and treat the mixtures of the body so as to avoid a harmful buildup of these residues within the soul.⁵⁶ 

In this infirm state, the imbalanced mixture of human nature requires a treatment that can first bring it back to its intended harmony—a state of eukrasia that preceded the primordial poisoning. Just as humans cannot sustain bodily life on their own but must rely also on external elements, neither can they achieve true health through any ordinary medical treatment. It makes sense, then, that Gregory proposes a solution for humanity's sickened condition by appealing to the Incarnation. The healing of dyskratic embodied souls requires a remedy that can flush the system of its toxic residues, rebalancing divine and human nature into its proper mixture. The perfectly balanced presence of divinity and humanity in one person suggested itself as an eukratic ideal for the possibility of harmony between spirit and flesh for all humanity.

Yet, about midway through the Oration, Gregory's section on the Incarnation does not seem principally concerned with disclosing in technical detail how this mixture took place in the person of Jesus. Instead, the guiding assumption of Gregory's medical anthropology seems to be that we can learn about God's nature, God's purpose, only if we first look inward and realize that “our nature was sick and in need of medical treatment.”⁵⁷ In short, God's healing, and so God's divinity, is made most tangible by means of proper medical diagnosis. Throughout much of the Oration, krasis functions as a way to diagnose the particular quality of human frailty in light of the ideal blend of human and divine in Christ. Yet Gregory leaves hints in these earlier sections that krasis will also serve as a mechanism for healing sick humans and in so doing making them more like Christ. Anticipating his concluding discussion concerning the Eucharistic bread as precisely this remedy, Gregory notes in section 27: “Certainly it was in keeping with Christ's intimate union (ἀνακίρναμαι) with our nature that he should be united (συνανάκρασις) with us in all our characteristics….The cleansing power (τὴν ἐκπλύνουσαν δύναμιν) had to penetrate it entirely. One part could not be healed by cleansing while another was overlooked and left uncured.”⁵⁸ He does not unpack here how the cleansing power is delivered and how it functions (this will come in the final section), but Gregory does imagine the catechumen as a medicalized Christian subject in need of an extraordinary remedy. What the Incarnation does for the healing and re-balancing of human nature writ large, the Eucharist does for each individual person.

The anthropological framework that opens the Catechetical Oration anticipates the elaborate system of medical knowledge through which Gregory imagines catechetical formation and describes the efficacy of the Eucharistic bread—a topic he considers at length in the chapter 37. And it is this remedying ritual of dietetics that serves as the climax of Gregory's presentation of humanity's diseased condition. Indeed, he refers to humanity as “the sick creature upon the earth,” one that requires a curative drug strong enough to traverse the catastrophic rupture between body and soul, humanity and divinity caused by Eden's poison.⁵⁹ This sick creature needed a remedy that could cleanse its decaying twofold nature, binding its physical and spiritual elements back together. The ritual substances of water, bread, and wine—imbued with pharmacological significance—provide this “cleansing power.” As we will see, then, the healing remedy of the Incarnation is materialized in the Eucharistic bread. Through this food, the ritual participant consumes an antidote. The matter of bread becomes a medical treatment that flushes out harmful residues, restores human nature to its proper balance and mixture, and prepares its temporary bodily congealment for the ongoing work of spiritual perfection. Gregory offers the bread as a physical remedy for spiritual ailments and a spiritual salve for the body's decay. If Eden's fruit has resulted in deadly residues—the undigested perittoma corroding humanity's elemental nature—then it is through divine dietetics that these dissolving elements are healed and bound back together.

Gregory's discussion of the Eucharist in chapter 37 of the Catechetical Oration combines the previous physiological, pharmacological, and dietetic considerations in its use of krasis to describe the medicinal function of the bread. Indeed, this section serves as the culmination and practical resolution of the anthropological reflections that preceded it. Gregory opens his consideration of the bread with terms relating to krasis to explain why this death-destroying bread is the only suitable remedy for the human condition:

A composite body requires a composite remedy. And the Eucharistic bread provides exactly that: healing divinity buried in mortal matter. The dissolution of the elements that hold human nature together was caused by a poison ingested through the mouth.⁶¹ The harmful and undigested residues produced by this poison have been corroding human nature ever since. And so, according to Gregory, the antidote for diseased bodies and their sick souls had to be an edible body untainted by that primordial poison. The edible body and the eating body communicate with one another and are transformed. The bread (this “other drug”) mixes its potency inside the body of the believer, beginning the process of becoming in which that body will one day attain its perfected spiritual form, blended in union with God.

I have used the translation above to indicate the ambiguity of meaning that occurs when modern interpreters attempt to fit Gregory's language neatly within English vocabulary that reflects the development of later Christological doctrine. “Union” appears pervasively here. But the Greek is not so easy to pin down. Terms linked to krasis open the passage and are found throughout the whole section, indicating a physiological chain reaction of blended essences that is initiated when one swallows the Eucharistic bread. Mixture is crucial to Gregory's anthropology as well as to his understanding of the Eucharistic bread's medicinal role. And it seems—at least in this important section—that medical reasoning precedes and structures Christological or theological speculation.

It is not that the bread unites the soul with the body, the human with the divine, in some generic spiritual sense. Rather, this doughy drug delivers the power of a healing antidote (ἡ τοῦ βοηθοῦντος δύναμις) into the body through the digestive tract, blending itself into the diseased elements of each person, knitting them back together, and thereyby counteracting the Edenic poison that so sickened human nature. Gregory says that those who are made sick by Eden's fruit seek an antidote that can “offset” its harmful effects. For this healing power of the bread, Gregory uses the verb σβέννυμι that is most properly translated as “quench.” Yet it carries with it connotations of the bread's effect upon the body's krasis, as it can also refer to a cooling or drying power. All of these senses indicate that the bread's salutary effect is in its capacity to rebalance the internal essences previously put in disarray by the toxic fruit of Eden. In other words, the target of the bread's power is specifically the body's mixture: its dyskratic state.

The effect of this highly technical discussion of bread as a medical intervention is that, in the absence of a more robust Christology, Gregory here plays with ideas common to pre-Chalcedonian Christological speculation—blending, union, mixture—by way of an elaborate physiological reflection on the drug effects of food.⁶² As Christ ate human food, indicating his full participating in the material existence of humanity, so too do humans eat a spiritual food, enabling their progress from mortality to divinity. The divinization of human nature, like the humanizing of divine nature, involves a proper mixture that begins in the digestive tract with the ingestion of a potent matter that will produce an eukratic state.⁶³ The Pauline movement from fleshy to spiritual, in Gregory's catechetical program, requires as a dietetic regimen.

Leveraging the power of food through dietetics is precisely the focus a few lines later as Gregory unfurls an elaborate theory of ritual bread-eating and its effects. This is premised on the logic, found elsewhere in Gregory's writing, that humans are formed by and identified with the particular food that they eat.⁶⁴ The same logic is at work as he describes why the spiritual healing of broken bodies must be delivered through the mouth, by means of a physical act of eating. Mortal bodies could not overcome death without first consuming something immortal, and so the body “must receive the life-giving power in the natural way.”⁶⁵ By eating the immortal food of God's body, the human body blends immortality within its mortal frame. The therapeutic system here is identical to the emphasis on krasis in Galenic method: doctors must treat the quality of a particular disease with a substance of the opposite quality.

Perhaps sensitive to the emphatic materialism structuring this line of argument, Gregory then pauses in order “to discuss the physiology of the body, so that our faith, in its concern for what is reasonable, may entertain no doubts on this question.”⁶⁶ The brief excursus into the body's physiology is Gregory's way of explaining the fundamental role of digestion in human formation, and that life cannot be sustained without “a power that enters it from the outside. This power is called food.”⁶⁷ Gregory's language about the power of food here reflects ancient traditions about the transformative effect of nourishment, found as far back as the Hippocratic treatise On Nutriment.⁶⁸ While each species is given its own particular diet by God in accordance with what it needs to sustain life, humanity is nourished first and foremost on bread.⁶⁹ The power supplied by bread's nourishment is not simply energy but rather the essential raw materials—the elements or particles (ὄγκοι)—that build bodies. When a person consumes the bread, Gregory argues, these nutritive food particles are transformed into blood and flesh and, through the power of digestion, give shape to the physical form.⁷⁰ For Gregory as well as medical writers stretching back to the Hippocratic tradition, the essential potency of food is that it enters the human body from the outside, reaches deep through the elements of human nature, and transforms the eater as it is itself transformed by digestion. Bread becomes body and body becomes bread.⁷¹ 

The Greek word Gregory uses for this digestive transformation, alloiotikos (ἀλλοιωτικός), is also found in medical texts discussing the power of food. It refers to the process of “becoming like another” that happens when we eat.⁷² In Gregory's physiological system we become the stuff of what we eat and that stuff becomes us. This framework takes on greater theological force when he turns back to an explanation of the Incarnation and how God and the Word were blended within human nature. He observes that

The blending of divinity and humanity in flesh requires that the material food digested within the Incarnate body be necessarily transformed as well. The Word of God is humanized through human food while humanity's food is divinized through a divine digestive tract. By eating bread, Christ's body becomes bread. By passing through Christ's body, bread itself is capable of becoming the body of Christ.⁷⁴ 

This, then, is the logic structuring Gregory's argument for the healing power of the ritual. Bread becomes the material manifestation of God's Word through the prayer of consecration and, as a result, it is the very means by which humanity ingests the healing power of divinity.⁷⁵ Yet in order to reach this conclusion, Gregory has constructed an elaborate medical and physiological system concerning blended natures: divinity and humanity in the person of Christ; body and soul in human nature; material food and divine remedy in the consecrated bread. The effects of this healing food upon human physiology draws Gregory's discussion of the bread to a close, bringing it back to the core concept that has guided it from the outset. He returns to the notion of krasis, suggesting that bread and wine supply the vital qualities of moisture and heat.⁷⁶ Flesh requires moisture (ὑγρός) to stave off its tendency toward desiccation, since it is dry and earthy (γεώδης) when left alone. Likewise, flesh requires heat to counteract the deathly chill that is characteristic of old age and declining health.⁷⁷ Even the flesh in which God dwelt possessed these elements and, in so doing, transformed bread and wine into a divine antidote for humans. This, Gregory explains, is how God provides healing to humans in the “natural way.”

Eucharistic eating, for Gregory, is in this sense a pharmacological intervention with the goal of tilting the human person from dyskrasia to eukrasia. The poisoned food of Eden resulted in humanity's dyskratic state of deteriorating health, a sickly condition due to an imbalanced mixture of hot and cold and dry and moist. The bread and wine of the Eucharist, by contrast, supply the divinely apportioned mixtures and so produce eukrasia, rebalancing those sickened elements of mortal life through a drug of immortality. The poison of Eden's fruit turns the soul to flesh. It has seeped deadly toxin into the human frame, accumulating harmful residues, and pulling apart its fibers. The flesh of God, in the form of bread, reverses this process, becoming a divine remedy that is “mixed into the bodies of those who believe” (τοῖς σώμασι τῶν πεπιστευκότων κατακιρνάμενος), knitting together their twofold natures, preparing them for the future work of spiritual transformation. By eating the bread of the Eucharist, the material elements of bodily life—these congealments of feeble flesh and diseased soul—are changed (μεταστοιχειόω) from a sick and mortal state into one that is well-balanced and better suited for immortality.⁷⁸ This ritual food, for Gregory, is the only possible remedy for the sick creatures of the earth. For it is the only one that has the power to address their composite nature—and in so doing, to bind what was frayed, to blend what was separated, and to heal what had become incurably ill.

Drug lore reminds us that matter has its own peculiar history. Cultures have long theorized and organized themselves in relationship to the potency of certain substances. My hunch is that, because they were embedded within the drug lore of Greco-Roman antiquity, the substances used in early Christian ritual represent just this kind of peculiar history. Late antique Christians famously emphasized the transformability (and deformability) of human nature. The unstable congealment of flesh and spirit that makes the human human was a touchstone in ascetic, doctrinal, speculative, practical, and liturgical/ritual writings. It is from this premise that the “material turn” in the study of Late Antiquity has generated such fruitful explorations into the vectors, modalities, risks, and potentialities of so situating the essential malleability of the human in relation to the material world. Food, and more specifically the medical use of food, represents a particularly provocative yet under-appreciated aspect of this material turn. As the writing of Gregory indicates, the material turn in our study of Late Antiquity ought to prompt a pharmacological turn: a burgeoning appreciation for and analysis of medicine's logic and medicine's application within Christian programs of human transformation. In this way, we might view the ritual use of medical remedies as a Christian materia medica leveraged for the healing, salvation, and divinization of embodied souls.

In the writings of philosophers, moralists, and poets, the physiological implications of dietetics—the precarious relationship between eating well and being well—was a powerful motif throughout Greco-Roman antiquity.⁷⁹ But for the catechist, dietetic regimens took on a particular urgency and a transcendent meaning. The ritualized antidote of the Eucharist situates the Christian within a regimen of health care—a regimen that helps to transform the sickly physical body into a healthy, spiritual, and divinized state. This is what we encounter in Gregory of Nyssa's Catechetical Oration. The healing power of consecrated bread, elaborated at length through a program of sacramental dietetics, reveals the intertwining of ritual efficacy and drug efficacy in Gregory's thought. And so the regimens of medical care were readily transferrable to the regimens of pastoral care administered in ritual practice. That the Eucharistic bread might be described as a drug and a cure was no mere literary flourish. It was a means of anchoring spiritual realities in the potencies of the material, sensible world.

Elsewhere, we find these sacramental rituals extended outside the liturgical context and modified to address other ailments. For if we are to take Gregory of Nazianzus at his word, late ancient Christians afflicted with chronic illness, whose physical pain had stretched beyond the limits of a doctor's care, sought healing directly from their God in the substances of bread and wine. Gorgonia, to name only one striking example, mingled her tears with the bread of the Eucharist and rubbed her aching body with it as a poultice. Or, as Virginia Burrus describes it: “a mingling of [Gorgonia's] own bodily fluids with Christ's body.”⁸⁰ The health of her soul, manifested by her hope in the matter of the bread, combined with the bread's divine power to restore the health of her body.⁸¹ The care of the body through pharmacology and the care of the soul through philosophy were not, in this way, distinct healing technologies. The transformation of the human person into her spiritualized ideal involved regimens combining the full range of medicine's art of healing.

In Gregory of Nyssa's Catechetical Oration, however, the reader encounters a more specific presentation of medical knowledge in which krasis is leveraged as an explanation for the meaning and efficacy of a ritual practice. This system provided the structuring logic for his understanding of human health and illness. It also enabled Gregory to reframe the ways in which sin and salvation register within the body. If humans are, by nature, a delicate balance of elemental qualities that are calibrated through dietetic regimens, then the transference of such regimens to the food and drink of the Eucharist must be viewed as an intensification (rather than a diminishment) of the material and medical significance of these substances.

From this vantage, the long-standing dismissal of medical reasoning and physiological digressions in early Christian literature as “mere metaphor” is in dire need of critical reassessment. Such flattened methodologies can only be sustained if the reader has decided from the outset that medicine is ancillary to the outlook of an author like Gregory, serving only as a rhetorical hook for more important theological and spiritual speculations. But I am not persuaded by this. The role of krasis in Gregory's Catechetical Oration reveals just how thoroughly invested some early Christian authors were in the power of medicine as an explanatory model, plotting a Christian subjectivity within a scientific discourse of illness, health, and healing. Indeed, far from a physical analogy for spiritual realities, medicine provided Gregory with a grammar and an epistemology for explaining the fundamental relationship between the spiritual and the material, the conditions of the cosmos and the human condition, and the dramatic encounter between humanity and divinity in the bread of the Eucharist. As a text aimed at “religious instruction,” Gregory embeds explanatory models drawn from medicine deep within the catechetical program of the Oration. These models help him to explain how human sin relates to human sickness. A robust account of the body's mixture becomes, for Gregory, a mechanism through which knowledge about drug lore and the medical potency of food might be leveraged to heal the poisoned soul.

What happens if we stop presuming that medicine serves only as a buttress for deeper theological commitments? What happens, instead, if we take the preponderance of technical medical knowledge deployed in late ancient literature as evidence of the suffusing reach of medicine within the conceptual categories, vocabulary, and regimens that came to be viewed as “orthodox” Christian belief and practice? In the case of the Oration, we would better discern how the ritual act of eating bread is, for Gregory, tantamount to the physical digestion of a divine remedy into one's deepest psychosomatic sicknesses. It is the ingestion of a singularly powerful medication that can heal the broken body bent towards death, a drug capable of reviving the sickened soul. The divinization of humanity, in this account, begins with a ritualized dietetic remedy aimed at producing a healthy mixture in both body and soul. This bread, then, was the only possible antidote for the sick creatures of the earth who still suffer the deadly effects of Eden's poison. In eating the Eucharistic meal, Gregory imagines the initiate beginning a dramatic transformation away from sickness and death, tilting decisively toward the good health of salvation. To eat like Christ ate, to eat what Christ ate, to eat (as it were) Christ himself—Gregory suggests that this is the first and necessary step on the journey from illness to wellness, from human disorder and imbalance to the perfect harmony and future blending of all things in God.