Augustine of Hippo : And the apostle: "if any man," he says, "think that he knoweth anything, he knoweth nothing yet as he ought to know. But if any man love God, the same is known of Him." He has not said, has known Him, which is dangerous presumption, but "is known of Him." So also in another place, when he had said, "But now after that ye have known God:" immediately correcting himself, he says, "or rather are known of God." And above all in that other place, "Brethren," he says, "I count not myself to have apprehended: but this one thing I do, forgetting those things which are behind, and reaching forth unto those things which are before, I press in purpose toward the mark, for the prize of the high calling of God in Christ Jesus." Perfection in this life, he tells us, is nothing else than to forget those things which are behind, and to reach forth and press in purpose toward those things which are before. For he that seeks has the safest purpose, until that is taken hold of whither we are tending, and for which we are reaching forth. — On the Trinity 9.1 John Chrysostom : "But if any man love God, the same," he doth not say, "knoweth Him," but, "is known of Him." For we have not known Him, but He hath known us. And therefore did Christ say, "Ye have not chosen Me, but I have chosen you." And Paul elsewhere, "Then shall I know fully, even as also I have been known." Observe now, I pray, by what means he brings down their high-mindedness. First, he points out that not they alone knew the things which they knew; for "we all," he saith, "have knowledge." Next, that the thing itself was hurtful so long as it was without love; for "knowledge," saith he, "puffeth up." Thirdly, that even joined with love it is not complete nor perfect. "For if any man thinketh that he knoweth any thing, he knoweth nothing as yet as he ought to know," so he speaks. In addition to this, that they have not even this from themselves, but by gift from God. For he said not, "hath known God," but, "is known of Him." Again, that this very thing comes of love which they have not as they ought. For, "if any man," saith he, "love God, the same is known of Him." — Homily on 1 Corinthians 20