11: Beloved, if God so loved us, we ought also to love one another. 12: No man hath seen God at any time. If we love one another, God dwelleth in us, and his love is perfected in us. 13: Hereby know we that we dwell in him, and he in us, because he hath given us of his Spirit. 14: And we have seen and do testify that the Father sent the Son to be the Saviour of the world. 15: Whosoever shall confess that Jesus is the Son of God, God dwelleth in him, and he in God. 16: And we have known and believed the love that God hath to us. God is love; and he that dwelleth in love dwelleth in God, and God in him. 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.
John calls on the believers to love on another. Its no good saying we love God if we do not love one another. We know that we are saved says John, if we have the Holy Spirit in us. John is not saying that we will come into judgment. He is saying that when the day of judgment comes we will have boldness before God because we are saved by the blood of Christ. We will have no fear of God because the love of God will flood our hearts by the Holy Spirit. Where there is love there can be no fear. Are you afraid of those who love you? No of course not. They have only your best interests are heart and there is nothing to fear in that. Then John bursts the bubble of the false professor He says if you say you love God but hate your brother then you are a liar. The commandment of God is very clear He who loves God must love his brother.