13 By this we know that we abide in him and he in us, because he has given us of his Spirit. 14And we have seen and testify that the Father has sent his Son to be the Savior of the world. 15 Whoever confesses that Jesus is the Son of God, God abides in him, and he in God. 16So we have come to know and to believe the love that God has for us. God is love, and whoever abides in love abides in God, and God abides in him. 17By this is love perfected with us, so that we may have confidence for the day of judgment, because as he is so also are we in this world. 18There is no fear in love, but perfect love casts out fear. For fear has to do with punishment, and whoever fears has not been perfected in love. 19 We love because he first loved us. 20 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. 21And this commandment we have from him: whoever loves God must also love his brother.