Gregory of Nyssa

The deepest mystic of the Cappadocians and the one Eastern Orthodoxy turns to when it talks about the soul's ascent to God. Life of Moses uses Moses going up Sinai as a model for every Christian's interior journey: the more you know God, the more you know how unknowable He is. That paradox — known precisely as unknowable — runs through every later Christian mystic, from Pseudo-Dionysius to Bernard to John of the Cross.