John Calvin Commentary 1 John 4:7

"Beloved, let us love one another: for love is of God; and every one that loveth is begotten of God, and knoweth God." — 1 John 4:7 (ASV)

Beloved. He returns to that exhortation which he enforces almost throughout the Epistle. We have, indeed, said that it is filled with the doctrine of faith and exhortation to love. He so dwells on these two points that he continually passes from one to the other.

When he commands mutual love, he does not mean that we fulfill this duty when we love our friends because they love us. Instead, as he addresses the faithful in common, he could not have spoken otherwise than that they should exercise mutual love. He confirms this statement with a reason often mentioned before: namely, because no one can prove himself to be a son of God unless he loves his neighbors, and because the true knowledge of God necessarily produces love in us.

According to his usual manner, he also contrasts this with the opposing statement: that there is no knowledge of God where there is no love. And he takes for granted the general principle or truth that God is love, that is, that his nature is to love humanity.

I know that many argue more subtly, and that the ancients especially distorted this passage to prove the divinity of the Spirit.

But the Apostle's meaning is simply this: since God is the fountain of love, this effect flows from him and spreads wherever the knowledge of him is found. This is similar to how he, at the beginning, called him light, because there is nothing dark in him; on the contrary, he illuminates all things by his own brightness.

Here, then, the Apostle does not speak of the essence of God, but only shows what he is found to be by us.

But two things in the Apostle’s words should be noted: that the true knowledge of God is what regenerates and renews us, so that we become new creatures; and that, consequently, it must conform us to the image of God. Away, then, with that foolish interpretation regarding unformed faith! For when anyone separates faith from love, it is as if he attempted to take away heat from the sun.