1John 4:8

“"God," then, being good, "is love," it is said. Whose "love worketh no ill to his neighbour," neither injuring nor revenging ever, but, in a word, doing good to all according to the image of God. "Love is," then, "the fulfilling of the law;" like as Christ, that is the presence of the Lord who loves us; and our loving teaching of, and discipline according to Christ. By love, then, the commands not to commit adultery, and not to covet one's neighbour's wife, are fulfilled.”

“But perchance some one may ask of us the same question which Hortensius asks in Cicero: If God is one only, what solitude can be happy? As though we, in asserting that He is one, say that He is desolate and solitary. Undoubtedly He has ministers, whom we call messengers. And that is true, which I have before related, that Seneca said in his Exhortations that God produced ministers of His kingdom. But these are neither gods, nor do they wish to be called gods or to be worshipped, inasmuch as they do nothing but execute the command and will of God.”

“What kind of love are we talking about here? It is the true love and not simply what people use this word to mean. It comes from our attitude and knowledge and must proceed from a pure heart. For there is also a love of evil things. Robbers love other robbers, and murderers love each other too, not out of love which comes from a good conscience but from a bad one.”

“Now see that to act against love is to act against God. Let no man say, "I sin against man when I do not love my brother, (mark it!) and sin against man is a thing to be taken easily; only let me not sin against God. How sinnest thou not against God, when thou sinnest against love? "Love is God." Do "we" say this? If we said, "Love is God" haply some one of you might be offended and say, What hath he said? What meant he to say, that "Love is God"? God "gave" love, as a gift God bestowed love. "Love is of God: Love Is God." Look, here have ye, brethren, the Scriptures of God: this epistle is canonical; throughout all nations it is recited, it is held by the authority of the whole earth, it hath edified the whole earth. Thou art here told by the Spirit of God, "Love is God." Now if thou dare, go against God, and refuse to love thy brother!”

“In what sense then was it said a while ago, "Love is of God;" and now, "Love Is God?" For God is Father and Son and Holy Ghost: the Son, God of God, the Holy Ghost, God of God; and these three, one God, not three Gods. If the Son be God, and the Holy Ghost God, and that person loveth in whom dwelleth the Holy Ghost: therefore "Love is God;" but "Is God," because "Of God." For thou hast both in the epistle; both, "Love is of God," and, "Love is God." Of the Father alone the Scripture hath it not to say, that He is "of God:" but when thou hearest that expression, "Of God," either the Son is meant, or the Holy Ghost. Because while the apostle saith, "The love of God is shed abroad in our hearts by the Holy Spirit which is given unto us:" let us understand that He who subsisteth in love is the Holy Ghost. For it is even this Holy Spirit, whom the bad cannot receive, even He is that Fountain of which the Scripture saith, "Let the fountain of thy water be thine own, and let no stranger partake with thee." For all who love not God, are strangers, are antichrists. And though they come to the churches, they cannot be numbered among the children of God; not to them belongeth that Fountain of life. To have baptism is possible even for a bad man; to have prophecy is possible even for a bad man. We find that king Saul had prophecy: he was persecuting holy David, yet was he filled with the spirit of prophecy, and began to prophesy. To receive the sacrament of the body and blood of the Lord is possible even for a bad man: for of such it is said, "He that eateth and drinketh unworthily, eateth and drinketh judgment to himself." To have the name of Christ is possible even for a bad man; i.e. even a bad man can be called a Christian: as they of whom it is said, "They polluted the name of their God." I say, to have all these sacraments is possible even for a bad man; but to have charity, and to be a bad man, is not possible. This then is the peculiar gift, this the "Fountain" that is singly one's "own." To drink of this the Spirit of God exhorteth you, to drink of Himself the Spirit of God exhorteth you.”

“For today the Holy Spirit came upon the disciples with a sudden sound, and changed the minds of carnal men into love of Him, and while tongues of fire appeared outwardly, their hearts were made flaming within, because as they received God in the vision of fire, they burned sweetly through love. For the Holy Spirit Himself is love. Hence John also says: "God is love." Therefore whoever desires God with a whole heart already has Him whom he loves. For no one could love God if he did not have Him whom he loves.”

“Why then does the one who does not love not know God? He confirms this in the following manner. God is love. For just as God is called goodness because in His goodness He created the intelligible and sensible world, so too, having sent His Only-Begotten Son into the world out of love for us, He showed through this that He is also love.”