Turner on the Platonic Contribution to Sethian Gnosticism

Finally, during the late first and throughout the second and third centuries, Neopythagorean and Platonic metaphysics made a strong impact on Sethianism. They served to structure its world of transcendent beings by means of ontological distinctions, and to explain how the plenitude of the divine world might emerge from a sole high deity by emanation, radiation, unfolding, and mental self-reflection. Neopythagorean arithmology helped to flesh out the various triadic, tetradic, pentadic, and ogdoadic groupings of the transcendental beings. Besides metaphysics, there was also at home in Platonism a by-now-traditional technique of self-performable contemplative mystical ascent toward and beyond the realm of pure being, which had its roots in Plato's Symposium (cf. 210A-212A). Interest in this technique shows itself in such figures as Philo, Numenius, the author(s) of the Chaldean Oracles, and in Plotinus. This technique not only supplemented earlier apocalyptic notions of ecstatic visionary ascent (perhaps associated with the spiritualized Sethian baptismal ritual as in Trimorphic Protennoia, Gospel of the Egyptians, Zostrianos, and perhaps in Marsanes), but it also created new forms apparently independent of such a baptismal context as in Allogenes and Three Steles of Seth. Most importantly, though, the older pattern of enlightenment through gnosis "knowledge," conferred by a descending redeemer figure, could be replaced by a self-performable act of enlightenment through contemplative or visionary ascent, whether for individuals (Allogenes and Marsanes) or for a community (Three Steles of Seth).

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