The motet Summus secretarius remains an enigma in the polyphonic output of the south Netherlandish composer Johannes Brassart (ca. 1400/5–1455). While extant sources (I-Bc Q15 and GB-Ob 213) attest to Brassart’s authorship, the message and function of this motet have long perplexed musicologists seeking to identify the work’s elusive subject and understand its cryptic language. Who is the “highest secretary” hailed at the outset, and what is this figure’s relationship to the biblical and cosmological references in the ensuing lines?
Summus secretarius reveals its secrets when examined within the context of the medieval cult of St. John the Evangelist. Taking cues from Brassart’s careful musical treatment of words quoted from the Gospel of John (1:1), we can decipher the motet’s language and symbolism using a diverse array of exegetical writings, images, and liturgical music that illuminate the unique status of John as Christ’s most intimate confidant, the seer and evangelist privy to his secrets. Brassart would have experienced the evangelist’s cult most vividly through his service as singer, chaplain, priest, and canon at the collegiate church of Saint-Jean l’Evangéliste in Liège—the most likely place for the motet’s composition and performance. Summus secretarius demonstrates to an exceptional degree the hermeneutic richness of enigmatic language in the unique texts of freely composed fifteenth-century motets.