Augustine of Hippo : And so a little after he says, "For he that loveth not his brother whom he hath seen, how can he love God whom he hath not seen"? because the reason that he does not see God is, that he does not love his brother. For he who does not love his brother, abideth not in love; and he who abideth not in love, abideth not in God, because God is love. Further, he who abideth not in God, abideth not in light; for "God is light, and in Him is no darkness at all." He therefore who abideth not in light, what wonder is it if he does not see light, that is, does not see God, because he is in darkness? But he sees his brother with human sight, with which God cannot be seen. But if he loved with spiritual love him whom he sees with human sight, he would see God, who is love itself, with the inner sight by which He can be seen. Therefore he who does not love his brother whom he sees, how can he love God, whom on that account he does not see, because God is love, which he has not who does not love his brother? — ON THE TRINITY 8.11 Augustine of Hippo : "If any man say, I love God." What God? wherefore love we? "Because He first loved us," and gave us to love. He loved us ungodly, to make us godly; loved us unrighteous, to make us righteous; loved us sick, to make us whole. Ask each several man; let him tell thee if he love God. He cries out, he confesses: I love, God knoweth. There is another question to be asked. "If any man say, I love God, and hateth his brother, he is a liar." By what provest thou that he is a liar? Hear. "For he that loveth not his brother whom he seeth, how can he love God whom he seeth not?" — Ten Homilies on 1 John 9 Augustine of Hippo : What then? does he that loves a brother, love God also? He must of necessity love God, must of necessity love Him that is Love itself. Can one love his brother, and not love Love? of necessity he must love Love. What then? because he loves Love, does it follow that he loves God? Certainly it does follow. In loving Love, he loves God. Or hast thou forgotten what thou saidst a little while ago, "Love is God"? If "Love is God," whoso loveth Love, loveth God. Love then thy brother, and feel thyself assured. Thou canst not say, "I love my brother, but I do not love God." As thou liest, if thou sayest "I love God," when thou lovest not thy brother, so thou art deceived when thou sayest, I love my brother, if thou think that thou lovest not God. Of necessity must thou who lovest thy brother, love Love itself: but "Love is God:" therefore of necessity must he love God, whoso loveth his brother. — Ten Homilies on 1 John 9 Augustine of Hippo : But if thou love not the brother whom thou seest, how canst thou love God whom thou seest not? Why does he not see God? Because he has not Love itself. That he does not see God, is, because he has not love: that he has not love, is, because he loves not his brother. The reason then why he does not see God, is, that he has not Love. For if he have Love, he sees God, for "Love is God:" and that eye is becoming more and more purged by love, to see that Unchangeable Substance, in the presence of which he shall always rejoice, which he shall enjoy to everlasting, when he is joined with the angels. — Ten Homilies on 1 John 9 Augustine of Hippo : Only, let him run now, that he may at last have gladness in his own country. Let him not love his pilgrimage, not love the way: let all be bitter save Him that calleth us, until we hold Him fast, and say what is said in the Psalm: "Thou hast destroyed all that go a-whoring from Thee" -and who are they that go a-whoring? they that go away and love the world: but what shall thou do? he goes on and says:-"but for me it is good to cleave to God." All my good is, to cling unto God, freely. For if thou question him and say, For what dost thou cling to Him? and he should say, That He may give me-Give thee what? It is He that made the heaven, He that made the earth: what shall He give thee? Already thou are cleaving to Him: find something better, and He shall give it thee. — Ten Homilies on 1 John 9 Bede : If anyone says, 'I love God,' etc. How do you prove that he is a liar? Listen: — Commentary on the Catholic Epistles Bede : For he who does not love his brother, etc. He who loves his brother loves God. It is necessary to love God in order to love love itself. For God is love. And lest anyone dare to say: "And what does it hinder to love God, even if I do not love my brother?" it is rightly added: — Commentary on the Catholic Epistles Cyprian : Also in the same place: "If any one shall say that he loves God, and hates his brother, he is a liar: for he who loveth not his brother whom he seeth, how can he love God whom he seeth not? " — Treatise XII Three Books of Testimonies Against the Jews Gregory the Dialogist : Why then is it first given to the disciples on earth, and afterward sent from heaven, unless because there are two precepts of charity, namely the love of God and the love of neighbor? The Spirit is given on earth so that the neighbor may be loved; the Spirit is given from heaven so that God may be loved. Therefore, just as there is one charity and two precepts, so there is one Spirit and two givings. First from the Lord standing on earth, afterward from heaven, because in the love of neighbor one learns how to arrive at the love of God. Hence the same John says: He who does not love his brother whom he sees, how can he love God whom he does not see? — Forty Gospel Homilies, Homily 26 Gregory the Dialogist : Hence it is that, as we have already said in another sermon, the same Spirit is read to have been given to the disciples twice: first by the Lord while dwelling on earth, afterward by the Lord presiding from heaven. On earth, indeed, he is given that neighbor may be loved; from heaven, truly, that God may be loved. But why first on earth, afterward from heaven, unless it is plainly given to understand that, according to John's voice, "He who does not love his brother whom he sees, how can he love God whom he does not see?" Therefore let us love our neighbor, brothers; let us love him who is near us, that we may be able to arrive at the love of him who is above us. — Forty Gospel Homilies, Homily 30