In verse 18 John goes on to say, “There is no fear in love, but perfect love casts our fear, because fear has punishment, and he who fears has not been perfected in love.” A literal translation of the first part of this verse would be, “Fear is not in the love.” “Fear” does not refer to the fear of offending God and being judged by Him (1 Pet. 1:17; Heb. 12:28), but to the fear that we have offended God and will be judged by Him. “Love” refers to the perfected love mentioned in the preceding verse, the love of God with which we love others. Perfect love is the love that has been perfected in us by our loving others with the love of God. Such love casts out fear and causes us to have no fear of being punished by the Lord at His coming back (Luke 12:46-47).
In 4:18 John tells us that he who fears has not been perfected in love. This means that the one who fears has not lived in the love of God so that it could be perfectly manifested in him.
First, John says in 4:12 and 17 that God’s love needs to be perfected in us. Then in 4:18 he speaks of being perfected in love. This indicates that we and the divine love are mingled. When love is perfected in us, we are perfected in love, for we become the love, and the love becomes us.
Verse 19 says, “We love, because He first loved us.” God first loved us in that He has infused us with His love and generated within us the love with which we love Him and love the brothers (v. 20). First John 4:20 says, “If anyone says, I love God, and hates his brother, he is a liar; for he who does not love his brother whom he has seen, cannot love God whom he has not seen.” He who hates a brother habitually proves that he is not abiding in the divine love nor in the divine light (2:9-11). When we abide in the Lord, we abide both in the divine love and in the divine light. We do not hate the brothers but love them habitually, living the divine life in the divine light and the divine love.
In 4:21 John says, “And this commandment we have from Him, that he who loves God love his brother also.” The commandment here is the commandment of brotherly love (2:7-11; John 13:34). It is possible to summarize John’s writing here in a simple way: God is love, and if we abide in Him, we shall love the brothers with Him as our love. This is John’s basic thought in these verses.
In 5:1 John goes on to say, “Everyone who believes that Jesus is the Christ has been begotten of God, and everyone who loves Him who begets, loves him who has been begotten of Him.” The Gnostics and Cerinthians did not believe in the identity of Jesus and the Christ. Hence, they were not the children of God, begotten of God. But whoever believes that the Man Jesus is the Christ, God incarnate, (John 1:1, 14; 20:31), has been begotten of God and has become a child of God (John 1:12-13). Such a one loves God the Father who has begotten him and also loves the brother who has been begotten of the same Father. This explains, confirms, and strengthens the word in the preceding verses (1 John 4:20-21).
In 5:1 we have an indication that brotherly love is actually a triangular love, that is, a love that involves three parties. As a child of God born of Him, we surely love our Father, the One who has begotten us. Then according to 5:1, if we love the begetting Father, we shall also love those who have been begotten of Him. Here we have a triangular love, a love involving God, ourselves, and those born of God. This triangular love is in the organic union with the very God who is love.
John emphasizes the divine birth (5:1; 2:29; 3:9; 4:7; 5:1, 4, 18). How is it possible for us to love God and to love others? This is possible only because we have had the divine birth. We have been born of God, begotten of Him, and because of this birth we are able to love others. As we have pointed out, this is a triangular love. Therefore, the triangular love is related to the divine birth. Everyone who believes that Jesus is the Christ has been begotten of God. Now we love not only the One who has begotten us, our begetting Father, but also the ones begotten of Him. This is the triangular love related to the divine birth as revealed in 5:1.