You may wonder why John wrote these letters. He answers this question very clearly in vs. 13: “I write these things to you who believe in the name of the Son of God, so that you may know that you have eternal life.” So, we know that John is writing to believers. He is writing to that community who profess Jesus as the Lord and Savior. He is writing to believers so that they would be assured that they have eternal life. Do you ever wonder if you will have eternal life? This verse assures us beyond a shadow of a doubt that we will have eternal life.
But there is more in this chapter. We read that those who are children of God do not sin. Wait, what? I sin, am I not a child of God? It seems like John says that. We should be used to this author making statements that stake a post in the ground and require that others measure themselves against that statement. I find myself falling short of that statement. And yet at the same time I know that I am a child of God and that God has forgiven me of that sin. I know that I have the Son and so as a result I have life. I praise God for that.
He ends this chapter and this letter by encouraging us to keep away from idols. Idols, those things which take the place of God in our lives. Those things that provide a barrier between us and God. Anything can do that, anything can be an idol. Just be aware of what is putting a barrier between you and God. Once you have identified it then you have identified an idol in your life.