The "Secret Gospel" (τὸ εὐαγγελικὸν μυστήριον) of Gregory of Nyssa

On this reading, the phrase “secret gospel” never properly belongs to a second Markan codex at all. It names, instead, a way of handling the one gospel that Alexandria inherited. Clement’s language in the letter to Theodore is the starting point. When he tells the story of Mark’s career, he does not say that Mark produced “a Secret Gospel.” He says that after Rome, in Alexandria, Mark composed a πνευματικώτερον εὐαγγέλιον, a “more spiritual gospel,” for the use of those being perfected, and even there did not commit “the unutterable things” to writing. The adjective is doing qualitative work. It marks a higher register of reading and teaching within one narrative stream, not the publication of a differently titled book. The only time “mystic gospel” appears as a quasi-title is in Clement’s account of the Carpocratians, and there it is treated as their label for what he calls an ἀπόγραφον—an inferior, derivative record that he explicitly denies is Mark’s.

That little word ἀπόγραφον carries a lot of weight. In the legal and administrative Greek of Clement’s world, an apograph is not the archetype; it is a transcript, a register, a derivative record that stands one step removed from the original. If you describe someone’s treasured “mystic gospel” that way, you are not quietly affirming a second Mark preserved among the pure. You are demoting your opponents’ book to the status of a notebook of excerpts, dictated recollections, or an unauthorized dossier. Clement’s oath language then makes sense: Theodore must never concede “their falsified assertion that the mystic gospel is Mark’s,” but must deny it even on oath. The secrecy being guarded here is not the existence of a hidden codex in the martyrium; it is the church’s right to define what counts as “Mark” and to insist that the true mystery associated with that name is not reducible to any rival publication.

The broader canonical politics of the period reinforce this trajectory. Paul’s phrase τὸ μυστήριον τοῦ εὐαγγελίου in Ephesians 6:19 was dynamite in Marcionite hands, because it could be read as pointing to a written “mystery-gospel” derived from Paul’s ascent to the third heaven and the ἄρρητα ῥήματα he heard there. Orthodox writers, acutely aware of that potential, tended either to domesticate the line (by making “gospel” mean preaching, with Luke as a tame stand-in) or to avoid the exact genitive construction. Origen begins to edge back into Pauline territory, speaking about a mystery of the gospel that will one day be proclaimed with full parrhesia when the church can bear it; but it is only once the fourfold canon has hardened into place that Gregory of Nyssa can speak freely of τὸ εὐαγγελικὸν μυστήριον—the “evangelic mystery”—without anyone thinking he is authorizing another gospel book. For Gregory, the “mystery” is the inner, liturgical depth of the same canonical narrative, unfolded in mystagogy and contemplation.

Gregory’s homily on Song of Songs 6 becomes especially interesting in this light. On the surface he is expounding a single verse, “My beloved went down into his garden,” but his exegesis quietly stitches together Johannine Logos theology, the Lukan Good Samaritan, and a descent-from-majesty motif that looks suspiciously like the reported opening of the Marcionite gospel. Jacob of Serug tells us that Marcion’s evangelion began with Christ appearing “between Jerusalem and Jericho,” a compressed prologue in which the katabasis of the Son is staged on that dangerous road. Gregory takes the same road and the same descent and reworks them as orthodox allegory: the Logos leaves “unapproachable majesty,” descends to the Adamic clay represented by the wounded man, and so initiates the drama of salvation. Whether or not there is direct textual dependence here is beside the point. What matters is that a motif that once functioned as the banner of a rival “mystic gospel” now lives inside the fourfold gospel as a layer of inner meaning—an “evangelic mystery”—available to those who have passed from the somatic to the spiritual reading.

On this reconstruction, there really is a “secret gospel” running from Mark through Clement, through a Theodore who might plausibly be Gregory Thaumaturgus, to Origen and Gregory of Nyssa. But it is not a bound codex hidden in the Church of St Mark. It is a disciplined way of reading the canonical narrative at two levels. The outer, somatic level is the familiar sequence of Jesus’ life, death, and resurrection, used to catechize and refute pagans and heretics. The inner level is the mystagogical and liturgical exposition—what Clement calls the μυστικὸν and πνευματικώτερον εὐαγγέλιον and what Gregory simply names τὸ εὐαγγελικὸν μυστήριον—which incorporates and domesticates themes that also circulated in Marcionite circles: descent and ascent, unspeakable words, the healing of Adam on the road between Jerusalem and Jericho. That inner “gospel” is secret in the sense that it is unwritten, or at least not fully systematized in public books; its proper medium is homily, catechesis, and sacramental practice.

Seen from that angle, the modern hunt for a physically separate “Secret Gospel of Mark” looks like a category mistake. The Alexandrians do not seem to be guarding an extra volume in a cupboard; they are guarding their claim to be the ones who know how to unlock the depths of the one gospel they actually read. The letter to Theodore, with its careful distinction between the church’s gospel and an alien ἀπόγραφον branded “mystic,” its insistence that the true mysteries remain ἄρρητα even within a πνευματικώτερον εὐαγγέλιον, and its oath-bound denial that Carpocratian books can be called Mark’s, fits perfectly into this pattern. Gregory of Nyssa’s talk of an “evangelic mystery” then shows what that pattern looks like once the dust of the canon wars has settled. The “secret gospel” survives, not as a lost codex waiting to be found, but as a way of reading the gospels that has long since been absorbed into the heart of orthodox mystagogy.