From one of his letters:
Thus understanding and love, that is, the knowledge of and delight in the truth, are, perhaps, as it were, the two arms of the soul, with which it embraces and comprehends with all saints the length and breadth, the height and depth, that is the eternity, the love, the goodness, and the wisdom of God. And what are all these but Christ? He is eternity, because “this is life eternal to know Thee the true God and Jesus Christ whom Thou hast sent" (S. John xvii. 3). He is Love, because He is God, and God is Love (1 S. John iv. 16). He is both the Goodness of God and the Wisdom of God (I Cor. i. 24), but when shall these things be? When shall we see Him as He is? For the expectation of the creature waiteth for the revelation of the sons of God. For the creature was subjected unto vanity, not willingly (Rom. viii. 19, 20). It is that vanity diffused through all which makes us desire to be praised even when we are blameable, and not to be willing to praise those whom we know to be worthy of it. But this too is vain, that we, in our ignorance, frequently praise what is not, and are silent about what is. What shall we say to this, but that the children of men are vain, the children of men are deceitful upon the weights, so that they deceive each other by vanity (Ps. lxi. 9; lxx.). We praise falsely, and are foolishly pleased, so that they are vain who are praised, and they false who praise. Some flatter and are deceptive, others praise what they think deserving, and are deceived; others pride themselves in the commendations which are addressed to them, and are vain. The only wise man is he who says with the Apostle: I forbear, lest any man should think of me above that which he seeth me to be or that he heareth of me (2 Cor. xii. 6).