How does I John 2:1 work for believers? One commentator talks of consent for the advocate to succeed but sometimes believers don't get convicted of their sins immediately, for example David in II Samuel 11 and 12. Does this mean his advocacy will not avail them? If they die, will they go to hell?
I John 2:1 cannot be taken in isolation. It is a continuation of what John talked about in chapter 1. "If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say that we have not sinned, we make Him a liar, and His word is not in us. My little children, these things I write to you, so that you may not sin. And if anyone sins, we have an Advocate with the Father, Jesus Christ the righteous. And He Himself is the propitiation for our sins, and not for ours only but also for the whole world" (I John 1:8-2:2).
When we sin, and we all do so, God requires that Christians confess their sins in order to be forgiven. The reason He can do so justly is that Jesus died for the sins of the whole world. The whole world will not be saved because the whole world will not turn to God. But for the Christian who has turned to God, and confesses his sins, Jesus speak on our behalf before the Father.
What happens if a Christian does not turn from his sins? Then we face God in Judgment concerning our sins. "For we must all appear before the judgment seat of Christ, that each one may receive the things done in the body, according to what he has done, whether good or bad" (II Corinthians 5:10). I cannot tell you what the end result of that judgment will be, since it has yet to take place. But knowing that the danger of hell exists, we seek all the more to help people out of sin. "Knowing, therefore, the terror of the Lord, we persuade men" (II Corinthians 5:11).
The fact that God is willing to forgive sin does not translate in a freedom to sin. Sin is going to happen in a Christian's life. Our goal is to avoid sins as best we can. "What shall we say then? Shall we continue in sin that grace may abound? Certainly not! How shall we who died to sin live any longer in it?" (Romans 6:1-2).