John Calvin Commentary 1 John 3:14

"We know that we have passed out of death into life, because we love the brethren. He that loveth not abideth in death." — 1 John 3:14 (ASV)

We know. He commends love to us by a remarkable eulogy, because it is evidence of a transition from death to life. It therefore follows that if we love the brethren we are blessed, but that we are miserable if we hate them. There is no one who does not wish to be freed and delivered from death.

Therefore, those who by cherishing hatred willingly give themselves up to death must be extremely stupid and senseless. But when the Apostle says that it is known by love that we have passed into life, he does not mean that man is his own deliverer, as though he could by loving the brethren rescue himself from death and procure life for himself.

For he does not here address the cause of salvation; rather, because love is the special fruit of the Spirit, it is also a sure symbol of regeneration. Thus, the Apostle draws an argument from the sign, and not from the cause. For as no one sincerely loves his brethren unless he is regenerated by the Spirit of God, he therefore rightly concludes that the Spirit of God, who is life, dwells in all who love the brethren. But it would be preposterous for anyone to infer from this that life is obtained by love, since love is, in order of time, subsequent to it.

The argument would be more plausible if it were said that love makes us more certain of life: then confidence as to salvation would rest on works. But the answer to this is obvious; for though faith is confirmed by all the graces of God as aids, it does not cease to have its foundation in the mercy of God only.

For instance, when we enjoy the light, we are certain that the sun shines; if the sun shines on the place where we are, we have a clearer view of it. But yet when the visible rays do not come to us, we are satisfied that the sun diffuses its brightness for our benefit. So when faith is founded on Christ, some things may happen to assist it, yet it still rests on Christ’s grace alone.