What does 1 John 4:17-21 mean?

¹⁷ Herein is our love made perfect, that we may have boldness in the day of judgment: because as he is, so are we in this world. ¹⁸ There is no fear in love; but perfect love casteth out fear: because fear hath torment. He that feareth is not made perfect in love. ¹⁹ We love him, because he first loved us. ²⁰ If a man say, I love God, and hateth his brother, he is a liar: for he that loveth not his brother whom he hath seen, how can he love God whom he hath not seen? ²¹ And this commandment have we from him, That he who loveth God love his brother also. (1 John 4:17-21 KJV)

The Consummation of Love

The apostle, having excited and enforced sacred love from the great pattern and motive of it—the love that is and dwells in God—proceeds to recommend it further by other considerations, and he recommends it in both its expressions: love to God and love to our brother or fellow Christian.

Love to God, the first and highest of all worthy objects, is love to the one who contains in himself all beauty, excellence, and goodness, and who gives to all other beings whatever makes them good and lovable. Love to God is here recommended for several reasons:

1. It gives us peace and confidence when we most need it—at the final judgment: “Herein is our love made perfect, that we may have boldness in the day of judgment” (1 John 4:17). There will be a day of judgment. Blessed are those who can face it with confidence, knowing Christ is their friend and advocate. Love assures us of God’s love in return, and of our friendship with Christ. The more we love God—especially knowing he sees our love—the more we trust in his love for us. “Hope does not disappoint us, because God’s love has been poured into our hearts through the Holy Spirit who has been given to us” (Romans 5:5). This hope and assurance are rooted in love: whether it is our love for God through the Spirit, or our awareness of his love for us, the result is the same—peace and joy in him. “Because as he is, so are we in this world” (1 John 4:17). Love makes us like Christ, and he will not deny his image. Love helps us suffer with Christ and gives us hope that we will be glorified with him (2 Timothy 2:12).
2. It removes the torment of fear: “There is no fear in love; but perfect love drives out fear” (1 John 4:18). Fear, understood here as dread of punishment, vanishes where love is mature. There is a difference between reverent fear of God—which is good and commanded (1 Peter 2:17; Revelation 14:7)—and a fear that is based on guilt and dread of God’s wrath. Love sees God not only as powerful but as good and loving through Christ. It brings joy and drives away fear, because “fear has torment.” The one who fears has not been made perfect in love. Let us long for the day when our love will be perfect and our joy complete.
3. It originates in God’s love for us: “We love because he first loved us” (1 John 4:19). His love is the reason and cause of ours. He loved us when we were unloving and unlovable, at great cost—the blood of his Son. He has pleaded with us to love him in return. Heaven and earth should be amazed at such love. His love birthed love in us. “We know that all things work together for good to those who love God, to those who are called according to his purpose” (Romans 8:28). This love is God’s doing: he called us, and by his Spirit, placed love for him in our hearts (2 Thessalonians 3:5).

Love to our brother and fellow believer in Christ is urged for several reasons:

1. It is consistent with our Christian profession. If someone claims to love God but hates his brother, “he is a liar” (1 John 4:20). How can someone hate the brother he sees and yet claim to love the God he hasn’t seen? The visible brother bears God’s image—how can someone claim to love the invisible original while hating the visible reflection?
2. It is commanded by God: “And this commandment we have from him: Whoever loves God must also love his brother” (1 John 4:21). God has shared his image both in nature and grace, and he expects our love to reflect that. We must love God supremely and others because they belong to God and are his children. Our Christian brothers and sisters have a new nature from God and share in his blessings. Loving them is a natural and necessary extension of loving God.