v 1 The church was characterized by its faith in Jesus as the Messiah, and Jesus promised that through him, as the Son of God, his followers could become sons of God as well. A key element in this is faith in him. The church was filled with the faithful, who were set apart from the faithless in the world. It was a much sharper distinction than today, as the decision to follow Christ was often met with steep opposition and persecution. So those who stayed in the church had to do so through faith, not just a family tradition or feeling of comfort.
John called the faithful to love one another as brothers in one family, all sons of the same Father. To be a Christian meant to love God, and here John continues insisting that the Christian must also love his brothers in the church.
v 2 Again John insists that to love God is to do what God commands, which includes loving the other Christians. They are not just any person, but sons of God himself, and therefore even more deserving of love. The love of a Christian is tested by how he treats the others. Not even in John’s time was being part of the church any guarantee of how a person lived, he still needed to have his actions tested.
v 3 To love God is to obey his commands. But so this doesn’t seem so much like an unsupportable burden, John reminds us that this is not impossible. It could feel impossible to his audience, having to live a life so different from their surrounding culture in so many details, having higher moral and ethical standards and doing many things the “hard way”. To adults, the idea of “obedience” is usually pretty foreign, and John was aware of this when he asked it of his flock.
v 4 Why was it possible to obey God’s commands? Because his audience was made up of children of God, who used their faith to overcome the world. Being a child of God means getting strength from him to continue growing to be ever more like him. John himself was a victor over the world, and was of the same shared faith as his audience. The battle continued even as he wrote but he said that the victory had already been given, a victory over worldly desires and a worldly lifestyle, a continuing and ongoing victory.
v 5 The key to victory was faith in Jesus as the unique Son of God. If Jesus was the Son of God, then everything that he taught was trustable. That meant that his promise of eternal life for the faithful, and judgement of the disobedient, called everyone’s actions into account on the final day. This would have been a huge motivator for the disciples because it was a double-edged sword – blessing as well as punishment. But on top of that, the deep love shown by Jesus’ willing self-sacrifice as God’s Son gave a deep emotional push to the Christians’ relationship with their maker and their obedience to him.
v 6 Water and blood: symbols of Jesus’ baptism and death, or death and life through the spirit. Blood and water came out of Jesus’ side when he was pierced on the cross (Jn 19:34). The Spirit is a witness: not the flesh. The Christians lived by a new set of rules that were very different than those of the world around them, and the other people did not understand the symbols of water or blood as did those of the Spirit. But, the Spirit is truth, even though the truth is contrary to much of common wisdom. (Help me on this verse!)
v 7 This verse was apparently added later on and was probably not in the original letter John wrote. “There are three witnesses in heaven: the Father, the Word, and the Holy Spirit, and these three are one. And three are the witnesses on the earth, (the Spirit, the water and the blood). Only four late Greek manuscripts have the verse, recorded from the fourteenth century to the present.
v 7-8 John was a witness, and called upon other witnesses to support what he had seen: the Spirit, the water and the blood. The irony of the life in the Spirit and the water is that it came only through the death symbolized by the blood. Just as Christ died, he calls his followers to die to their old life through baptism and to begin a new life through the Spirit in communion with his blood.
v 9 Testimony about Jesus came from the men and women who were with him, but also through God himself, who asserted that Jesus was his son. That testimony came from God to man through the Spirit and the changed lives of those who followed Jesus. (Jn 1:32-34, 8:47, Lk 3:21-22, 9:35) The testimony was also understood individually by the people who responded to the Christians’ message and converted to faith in Christ.
v 10 In becoming a Christian, a person came to believe in God and Jesus as his son, and changed his heart dramatically in response to the love shown by God’s willing sacrifice of his son and Jesus’ willingness to submit for the benefit of others. This faith and change of attitude were the testimony of the heart of a Christian. On the other hand, those who did not believe in God, and consequently in Jesus, his Son, were denying what God said about Jesus. This made God out to be a liar, (v 1:10) and was a grave error on the part of the unbeliever. Each believer and every person should mind what God says and not try to oppose him (parable of the warring kings).
v 11 Explanation of God’s testimony: eternal life through his Son. God gives it to his children, the Christians, (Jn 1:12-13) and does so solely through Jesus (Jn 14:6).
v 12 To have the son of God is to have an intimate relationship with him, that is, to be one of Christ’s disciples. Life is eternal life forever with God in heaven, as well as meaning, purpose and joy in the Spirit even amidst suffering in life here on the earth. These are privileges of Christians only, not enjoyed by those who do not know God.