17 This way, love has the run of the house, becomes at home and mature in us, so that we're free of worry on Judgment Day - our standing in the world is identical with Christ's. 18 There is no room in love for fear. Well-formed love banishes fear. Since fear is crippling, a fearful life - fear of death, fear of judgment - is one not yet fully formed in love. 19 We, though, are going to love - love and be loved. First we were loved, now we love. He loved us first. 20 If anyone boasts, "I love God," and goes right on hating his brother or sister, thinking nothing of it, he is a liar. If he won't love the person he can see, how can he love the God he can't see? 21 The command we have from Christ is blunt: Loving God includes loving people. You've got to love both.
Matthew Henry's Commentary on 1 John 4:17-21
Commentary on 1 John 4:14-21
(Read 1 John 4:14-21)
The Father sent the Son, he willed his coming into this world. The apostle attests this. And whosoever shall confess that Jesus is the Son of God, God dwelleth in him, and he in God. This confession includes faith in the heart as the foundation; makes acknowledgment with the mouth to the glory of God and Christ, and profession in the life and conduct, against the flatteries and frowns of the world. There must be a day of universal judgment. Happy those who shall have holy boldness before the Judge at that day; knowing he is their Friend and Advocate! Happy those who have holy boldness in the prospect of that day, who look and wait for it, and for the Judge's appearance! True love to God assures believers of God's love to them. Love teaches us to suffer for him and with him; therefore we may trust that we shall also be glorified with him, 2 Timothy 2:12. We must distinguish between the fear of God and being afraid of him; the fear of God imports high regard and veneration for God. Obedience and good works, done from the principle of love, are not like the servile toil of one who unwillingly labours from dread of a master's anger. They are like that of a dutiful child, who does services to a beloved father, which benefit his brethren, and are done willingly. It is a sign that our love is far from perfect, when our doubts, fears, and apprehensions of God, are many. Let heaven and earth stand amazed at his love. He sent his word to invite sinners to partake of this great salvation. Let them take the comfort of the happy change wrought in them, while they give him the glory. The love of God in Christ, in the hearts of Christians from the Spirit of adoption, is the great proof of conversion. This must be tried by its effects on their temper, and their conduct to their brethren. If a man professes to love God, and yet indulges anger or revenge, or shows a selfish disposition, he gives his profession the lie. But if it is plain that our natural enmity is changed into affection and gratitude, let us bless the name of our God for this seal and earnest of eternal happiness. Then we differ from the false professors, who pretend to love God, whom they have not seen, yet hate their brethren, whom they have seen.