1 John 4:19 (BSB)

We love because He first loved us.

From 1 John 4. Also in the ESV.

Commentary on 1 John 4:19

• John Calvin (Reformed), Calvin's Commentaries on 1 John 4:19: 19 We love him The verb ἀγαπῶμεν may be either in the indicative or imperative mood; but the former is the more suitable here, for the Apostle, as I think, repeats the preceding sentence, that as God has anticipated us by his free love, we ought to return to render love to him, for he immediately infers that he ought to be loved in men...
• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on 1 John 4:17-21: The apostle, having thus excited and enforced sacred love from the great pattern and motive of it, the love that is and dwells in God himself, proceeds to recommend it further by other considerations; and he recommends it in both the branches of it, both as love to God, and love to our brother or Christian neighbour. I.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on 1 John 4:19: We love him, because he first loved us. Lest love to God, and so to one another, should be thought to be of ourselves, and too much be ascribed unto it, the apostle observes, that God's love to us is prior to our love to him; his love is from everlasting, as well as to everlasting; for he loves his people as he does his...
• Albert Barnes (Presbyterian), Barnes' New Testament Notes on 1 John 4:19: Verse 19. We love him, because he first loved us. This passage is susceptible of two explanations; either (1.) that the fact that he first loved us is the ground or reason why we love him, or (2.) that as a matter of fact we have been brought to love him in consequence of the love which he has manifested towards us, though the real...