John Calvin's Commentary on the Bible

7 (1 John 4:7)

Verse 7

7Beloved 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. On these two points he so dwells, that he continually passes from the one to the other.

When he commands mutual love, he does not mean that we discharge this duty when we love our friends, because they love us; but as he addresses in common the faithful, he could not have spoken otherwise than that they were to exercise mutual love. He confirms this sentence by a reason often adduced before, even because no one can prove himself to be the son of God, except he loves his neighbors, and because the true knowledge of God necessarily produces love in us.

- John Calvin's Commentary on the Bible