Historians of Islam during its formative period have a strong tendency to focus their attention on Muslim elites—who were a minority—at the expense of non-Muslim subjects of the caliphate—who were a majority. In Between Christ and Caliph, Lev Weitz reframes the historical narrative about the emergence of Islam by placing non-Muslims at the center of this narrative, with special attention to the field of law. He argues that Christian, Muslim, and other elites were part of what Hodgson called an “Islamicate” culture that was shared by all subjects of the caliphate. He asks: How did Christians respond to Islamic legal institutions and practices and what effect did this response have on legal institutions and communal identity? He answers: Islamic imperial governance motivated Syriac Christian elites to modify their communal institutions and to redefine their identity as religious communities by creating a new Christian law that treated obligations between husbands, wives, and other family members as defined by new rules relating to marriage, divorce, inheritance, and the household (baytā). The argument unfolds in three parts of uneven length that are framed by an introduction and conclusion: Part I, Empire, Household, and Christian Community from Late Antiquity to the Abbasid Caliphate (chapters 1–3); Part II, Christian Family Law in the Making of Caliphal Society and Intellectual Cultures (chapters 4–8); and Part III, Islamic Family Law and Christian Jurists after Imperial Fragmentation (chapter 9). Each chapter begins with a short selection from a Christian legal source that exemplifies the problematic of that chapter.

In Chapter 1 Weitz reviews the position of the Church on monogamy and the indissolubility of marriage as reflected in the New Testament, second-century church orders, and the proceedings of ecumenical synods in the fourth and fifth centuries, followed by a review of Christian marriage practices in Byzantium and the Sassanian empire.

In Chapter 2 Weitz argues that during the early Islamic period, church leaders placed a new emphasis on the connection between ecclesiastical authority and believing households, thereby “Christianizing” the institution of marriage. The earliest example of this new trend is evidenced in the writings of Jacob of Edessa (d. 708), who assembled a collection of ecclesiastical rulings that contributed to the creation of a comprehensive Christian civil law tradition. As the initially fluid and porous communal boundaries between Christians and Muslims began to harden, church leaders struggled to prevent Christian women from marrying Muslim men and Christian men from taking multiple wives. In his Canon, the East Syrian patriarch George I (r. 660-680) took the bold step of proclaiming that ecclesiastical law and priestly ritual confer legality on sexual unions between laypeople. Whereas previously marriage had been a civil institution within which spouses were expected to behave in appropriate ways, it was now becoming a legal institution that was newly subject to Christian law (nāmosā krēsṭyānā). Like baptism and the Eucharist, marriage became a ritual practice that facilitated membership in the community.

In Chapter 3 Weitz discusses the genre and general contents of Christian lawbooks composed by bishops/jurists in response to the challenges of Islamic institutions. By turning to a new textual genre, that of the lawbook, Christian scholars introduced a coherent religious communal law. Many of the topics dealt with in these lawbooks will be familiar to students of Islamic law. Examples of such lawbooks include: the Jurisprudential Corpus of Ishoʿbokt (ca. 770), which contains chapters on legal theory, marriage, divorce, inheritance, contracts, and procedure; the Lawbook of the East Syrian patriarch Timothy I (r. 780-823), which deals with marriage, divorce, and inheritance; the Lawbook of Ishoʿbarnum (r. 823-828), which treats marriage, divorce, inheritance, slavery, loans, debt, and theft; the Order of Marriage and Inheritance by ʿAbdisho bar Bahriz of Mosul (mid-9th-century), which introduces a new system of inheritance; and a systematic compendium of East Syrian law, arguably the first of its kind, compiled by Gabriel of Basra (fl. late ninth century). By bringing marriage, inheritance, and property rights into a single regulatory regime, Weitz argues, church leaders put forward a new understanding of the Christian patrilineal household—the baytā—as a social institution.

Part II is devoted to the details of Syriac family law. In Chapter 4 Weitz outlines the general features of this law as follows: marriage is a contract (tanway) that requires the consent of the parents; this contract is, in theory, indissoluble, although a wife may leave her husband if he rejects God or engages in sorcery or murder, and a husband may leave his wife if she is disobedient; a husband’s financial obligations include the marriage portion and maintenance, in return for which a wife owes her husband obedience; property passes from father to son, although wives and daughters are entitled to specific shares of the estate. In constructing this law, Weitz argues, bishops drew on a wide range of “ancient”—albeit unspecified—legal materials and customary legal instruments that they “repackaged” as Christian tradition.

In Chapter 5 Weitz argues that the “imbrication” of Christian family law within the Islamic state affected social relations between and among Christians and the very identity of Christians themselves. For example, a Christian man who found himself in an unwanted marriage but was unable to secure a Christian divorce might approach a qāḍī to secure an Islamic divorce. This is one of several examples of how differences between Christian and Islamic marriage laws created a “structural incentive” for Christian men who wanted a divorce to leave the Christian community.

In Chapter 6 Weitz argues that the modes of legal reasoning developed by Christian bishops to deal with subjects such as incest were shaped by a broad realignment of attitudes towards the relationship between reason and revelation that was undertaken not only by Muslims but also by Christians and Jews. For example, Karaites such as ʿAnan ben David (d. ca. 795) and Benjamin al-Nahawandi (mid-ninth century), and the East Syrian Patriarch Timothy I (d. 823), all applied analogical reasoning to incest prohibitions, drawing on tools developed by Muslim jurists. Weitz outlines the progression of this broad cultural realignment as follows: Muslim jurists adopted and repurposed modes of reasoning used by earlier Christian and Jewish thinkers; Christians and Jews then began to incorporate the methods of Islamic legal reasoning into their legal repertoires; with the result that Christian and Jewish thinkers, like their Muslim counterparts, were compelled to reconsider the relationship between scripture and tradition, on the one hand, and human reason, on the other. The positions adopted by these elites determined the respective profiles of Islam, Judaism, and East-Syriac Christianity in the Mountain Arena.

In Chapter 7 Weitz treats inter alia the practice of concubinage. It may come as no surprise that Christian men took slave women as concubines, which was a standard strategy of biological and social reproduction among Muslim elites. In an effort to deter Christian laymen from engaging in this practice, bishops would disinherit any child born from such a union, thereby “trimming” the Christian family tree and, in the process, defining a distinctive Christian household form and a model of lineage reproduction. Again, however, a “structural incentive” came into play: a Christian man who objected to the disinheritance of his children might approach a qāḍī and seek to overturn the ruling of the Christian bishop.

In Chapter 8 Weitz treats interreligious marriage. In both Islamic law and Christian law, one unstated goal of restrictions on out-marriage by females is to maximize the reproductive capacity of women in the service of the religious community. Weitz argues that over the long term, the reproductive capacity of Muslims was greater than that of Christians because the Islamic state and its courts, headed by the caliph, were better situated than Christian authorities to prevent women from marrying outside the community.

In Part III (Chapter 9) Weitz compares “Christian Sharīʿa” and Islamic fiqh in what he calls the “later medieval period.” He argues that West Syrian jurists commonly applied the rules of Islamic inheritance law and that West Syrian scribes essentially translated these rules into Syriac. By contrast, East Syrians drew on their own resources and developed their own inheritance law, which bears little or no relation to Islamic inheritance law. One wonders about the reasons for this difference. Be that as it may, Weitz also undertakes a comparison of al-Ghazālī’s (d. 1111) al-Wasīt and Bar Ebroyo’s (d. 1286) Nomocanon. Based on his analysis of these two texts, Weitz concludes that Bar Ebroyo modeled his treatise on that of al-Ghazālī while at the same time reconfiguring Islamic norms for a Christian audience.

My one criticism relates to Weitz’s use of the term “medieval”—early, middle, and late—as it relates to Islamic history. In my view there is nothing “medieval” about Muḥammad, the rise of Islam, or the history of Islam between 610 and ca. 1250. Be that as it may, Garth Fowden recently has proposed a new way of conceptualizing the history of the Mountain Arena during this period. In Before and After Muḥammad: The First Millenium Refocused (Princeton, 2014), Fowden argues that the millennium between Jesus of Nazareth and Ibn Sīna or Avicenna (d. 1037) constitutes a coherent chronological unit during which the inhabitants of the Mountain Arena—pagans, Christians, Jews, Manichaens, Zoroastrians, and Muslims—were engaged in a common intellectual exercise, namely, exploring the nature of prophecy, scripture, and exegesis. Notably, Fowden includes law under the category of exegesis and he proposes that legal systems that operate within the same society will naturally manifest shared areas of interest, such as those documented by Weitz. It is thus regrettable that Weitz makes no attempt to link his “integrative” history of law to the multi-cultural and multi-confessional perspective put forward by Fowden.

This criticism should not detract from the importance of Between Christ and Caliph, a sophisticated and well-written monograph that is a product of wide reading in Arabic and Syriac sources. In the future, historians will want to build upon Weitz’s integrative approach and apply it to other legal systems that flourished in the Mountain Arena during the first millennium. Setting the agenda for future scholarship is no small accomplishment and Weitz is to be congratulated for his efforts.