Here and often in the New Testament there are two ways in which the experience of the Christian is described -we in God and God in us (3:24), we in Christ and Christ in us. Our life is in God, in Jesus Christ, abiding in Him (look back to 2:6 and 24). God is in us, Jesus Christ is abiding in our lives. As our bodies live and move in the air which we breathe and the air is in us, supporting our life, so the Christian's life is in Christ. We depend on Him for spiritual life as we depend on the air we breathe for physical life. He is our very life. Equally wonderful is it that He is in us. If we let Him, He makes His home in us by the Holy Spirit. The apostle Paul expresses this by saying that our bodies are temples of the Holy Spirit (1 Corinthians 6:19).
Two things give us confidence and help us to 'know that we abide in Him and he in us.' One is that we know and believe what God has done for us in His Son Jesus Christ. This is faith, the foundation for building up the Christian life. The other is that we experience the love of God in us and are able to express this to others. This love is like the building itself, based on that foundation of faith. Both faith and love are possible by the work of the Holy Spirit. So verse 13 says that 'we know' that Christ is ours and we are His 'because he has given us of his own Spirit'.
A building that is of any worth must have good foundations and a good structure built on the foundations. The Christian life may be tested by its foundation of faith and its structure of love. The two things - these two tests of the reality of Christian life - dealt with separately in the earlier part of the letter, are now brought together.
Christian faith is not just a matter of our experience. It is based on the love of God. That love of God is not just a feeling we can have. It has been expressed in history in the acts of God and most of all in that 'the Father has sent his Son as the Saviour of the world'. There are times when faith would be sorely tested if it depended only on experience and on feeling. It depends, rather, on what God has done. Therefore it was most important for the apostles and early disciples of Jesus to be able to say, 'We have seen and testify' that this is so. As was emphasized in 1:1-3, there were those who saw with their eyes, heard with their ears, touched Jesus of Nazareth. They knew from those years with Him that He was truly Man, but He was more than man; He was the Son of God, sent to be the Saviour of the world. They were so certain that they could not be silent, even if they should die for their faith. When the Jewish leaders tried to silence them in the early days, all they could do was to answer, 'we cannot but speak of what we have seen and heard' (Acts 4:20). We accept their witness and on the basis of it, and on the strength of all that God has done in the lives of believers since; we confess that 'Jesus is the Son of God'. That confession is most important for us. It is such faith that changes all life for us. It is faith in Jesus Christ as Saviour, not just as Saviour of the world, but our Saviour. It is belief in Jesus Christ as Son of God, but also trust in Him as our Lord and God. This is the rock foundation, of our Christian life.
On the foundation of such faith the Christian life is built. The building is God's building. He builds it. He is in it. Because 'God is love', the building must be love. There nothing that is more important than this about the building material of the Christian life and the way it is seen by the world. We go back to the words of Jesus: 'By this all men will know that you are my disciples, if you have love for one another' (John 13:35). We also go back to the fact that God in us, by His Holy Spirit, makes that love possible. 'The fruit of the Spirit is love' (Galatians 5:22). 'God's love has been poured into our hearts through the Holy Spirit which has been given to us' (Romans 5:5). This is how the Christian, life is different, by love being in our hearts and shown in our lives. Such love is not natural to us, self-centred men and women as we are. It is built into us when the Holy Spirit lives in us and is allowed to be the Builder.
The apostle Paul speaks of the Christian life as a matter of 'faith working through love' (Galatians 5:6). If we a not sure of our faith and do not know God's love as active in us, then we cannot be sure of our Christianity. When we know that sincere faith and love are in us, we can be confident. It is not a confidence in ourselves, but in God and that He by His Spirit is active in our lives. Read and ponder again the way verses 13-16 emphasize this.
Lord of truth and love, we thank You that You have made Your way plain to us and have shown us that You have given Your Son to be the Saviour of the world. We thank You for those who have believed in You in all ages in the past and for those in every part of the world today who believe in You. Help us also to believe and by Your Spirit to live in love that the world may see something of Jesus Christ in us, and. that we may be sure that it is You who are at work in us, for this is Your purpose now and always. AMEN.
1. What does it mean, when it says that God sent His Son to be Saviour? Look up Matthew 1:21, Luke 19:10, John 4:42, and 1 Timothy 1:15, as well as any other passages that speak of God's salvation in Jesus.
2. We have noted in earlier studies that 'the world' has two rather different meanings - firstly in 2:2 and John 3:16, then in 2:15-17. What then do you think it means that Jesus was sent to be the Saviour of 'the world'?
3. The work of the apostles was to see and to testify 'that the Father has sent His Son as the Saviour of the world'. Have we any similar task and responsibility to the world - the world around us? The whole wide world?
Note.In verse 16 most translations, like the R.S.V., speak of `the love God has for us'. It is literally 'the love God has in us', reminding us again that God not only loves us, but wants to put His love in us and He does this as we let Him come into our lives.