John makes it clear in chapter four that some are denying that Jesus came into the world in the flesh. Presumably they were members of one of the heretical groups that claimed Jesus was not physical but a spirit being. We know from the later centuries that Gnostic groups believed that the flesh is evil and only the spiritual realm is pure. They believed that Jesus could not have been a human because then he would have been, by nature, corrupt. Unfortunately, some groups today still act as though our physical bodies are, by nature, of a lesser importance than our spirits or souls. The biblical witness is consistent in stating that Jesus will return and bodily resurrect people to a new life with a new body. We will not be disembodied beings but new creations with physical bodies. It is though a spirit that makes our bodies holy – Holy Spirit.
John’s letters are “love letters” in the sense that he emphasises love for one another again and again. This love is based on our identity in Christ and flows out to all those who have the Spirit of God in them. This love is coupled with our love for God which exhibits itself in love for the people of God. He concludes his letter by admonishing Christians not to sin because those who are born of God do not sin. Let us love one another and keep one another from sin.