By this we know that we love the children of God, when we love God, and keep his commandments.
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Augustine of Hippo
AD 430
In this we know that we love the sons of God. 1 John 4:2 What is this, brethren? Just now he was speaking of the Son of God, not of sons of God: lo, here one Christ was set before us to contemplate, and we were told, Whosoever believes that Jesus is the Christ is born of God: and every one that loves Him that begot, i.e. the Father, loves Him also that is begotten of Him, i.e. the Son, our Lord Jesus Christ. And he goes on: In this we know that we love the sons of God; as if he had been about to say, In this we know that we love the Son of God. He has said, the sons of God, whereas he was speaking just before of the Son of God— because the sons of God are the Body of the Only Son of God, and when He is the Head, we the members, it is one Son of God. Therefore, he that loves the sons of God, loves the Son of God, and he that loves the Son of God, loves the Father; nor can any love the Father except he love the Son, and he that loves the sons, loves also the Son of God. What sons of God?...
In this we know that we love the children of God, (that is, all men, and especially the faithful, who are made his adoptive children) when we love God, and keep his commandments, for these two branches of charity, the love of God and of our neighbour, are inseparable: the one is known and proved by the other. (Witham)
