Augustine of Hippo

And indeed pride, although it be in itself a great sin, is of such sort in itself alone apart from others, that it for the most part follows after and steals with more rapid foot, not so much upon sins as upon things which are actually well done. …

On Nature and Grace ↗

Bernard of Clairvaux

Both meditated iniquity, affecting height: the one, of power; the other, of knowledge. For the foolish woman believed him who promised, but who was deceiving: "You shall be as gods, knowing good and evil." Had he not already first deceived himself, he who had persuaded himself that he would be like the Most High? For he who thinks himself to be something, when he is nothing, deceives himself.

Sermons on the Song of Songs, Sermon 69 ↗

Bonaventure

Adam with his wife contracted the vice of curiosity, when the devil said to them: "You shall be as gods, knowing good and evil": he also contracted the vice of carnality, when he ate of the fruit: he also contracted the vice of vanity, when he wished to be as gods. Hear, brothers: those who have the knowledge of the Saints, namely clerics, let them take heed for themselves, lest they have anything of vice mixed in; because if a man mixes in anything of vice, he loses the knowledge of discerning between good and evil.

Collationes de Septem Donis, Collation 4 ↗