Read 1 John 4:7-21
7 Dear friends, let us love one another, because love comes from God. Whoever loves is a child of God and knows God. 8Whoever does not love does not know God, for God is love. 9And God showed his love for us by sending his only Son into the world, so that we might have life through him. 10This is what love is: it is not that we have loved God, but that he loved us and sent his Son to be the means by which our sins are forgiven.
11 Dear friends, if this is how God loved us, then we should love one another. 12No one has ever seen God, but if we love one another, God lives in union with us, and his love is made perfect in us.
13 We are sure that we live in union with God and that he lives in union with us, because he has given us his Spirit. 14And we have seen and tell others that the Father sent his Son to be the Saviour of the world. 15If anyone declares that Jesus is the Son of God, he lives in union with God and God lives in union with him. 16And we ourselves know and believe the love which God has for us.
God is love, and those who live in love live in union with God and God lives in union with them. 17Love is made perfect in us in order that we may have courage on Judgement Day; and we will have it because our life in this world is the same as Christ’s. 18There is no fear in love; perfect love drives out all fear. So then, love has not been made perfect in anyone who is afraid, because fear has to do with punishment.
19 We love because God first loved us. 20If we say we love God, but hate our brothers and sisters, we are liars. For people cannot love God, whom they have not seen, if they do not love their brothers and sisters, whom they have seen. 21The command that Christ has given us is this: all who love God must love their brother or sister also.
This passage is very simple - because God has loved us we should also love. But in truth, loving is really difficult. The love of Christ is self sacrificial, painful - the example we ought to follow. Christians too easily opt for easy love - being with people we like rather than those that challenge us to love as Jesus loved.