Summary: Stop sinning, apologize for what you've done, now.
8 If we claim to be without sin, we deceive ourselves and the truth is not in us. 9 If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness. 10 If we claim we have not sinned, we make him out to be a liar and his word is not in us.
8. Here John says that those who claim to be without sin do not have the truth in them. This lack of truth applies to the saved believer who claims to have been freed from all sin in their present life. A believer should recognize his or her sinfulness and need of forgiveness through Christ.
As stated in verse 7, we don't lose hope, but we trust in Christ to forgive us. When we say that we trust we’ll be forgiven; this means that we know we have sinned against Christ.
9.when we accept our sins and we are ready to apologize and we regret for our sins, then we are forgiven and if we don’t apologize, we are someone who is not born again, that if you would acknowledge your sin and your need for a savior then God is faithful to forgiven you and cleanse you of, not just your past sins, but all of your past and future sins once and for all time!
It is not to be applied to a believer saying they have to be continually forgiven and cleansed of sin, since this completely undermines the very heart of the Gospel and the sacrifice of Christ. But it is to be applied to unbelievers who don’t believe in sin and therefore do not cry out to a savior to forgive and cleanse them of all sin.
10. No one can ever say that he never sinned.
As it is written in Psalms 51:5 Surely I was sinful at birth, sinful from the time my mother conceived me.
Only by faith can lost sinners be justified. Only someone born of the Spirit can enjoy fellowship with the Father and walk in His marvellous light. Only those who are saved by grace through faith in Christ, are forgiven of all their sin and declared righteous in the sight of God. How we praise our heavenly Father that at the moment of our salvation, past, present, and future sins are forgiven forever, and will be remembered no more.
The fact that Jesus is the eternal Son of God. God’s truth is presented as “light,” while false teachings are presented as “darkness.” Those who hold to the truth are saved from sin; those who claim to have no sin at all are self-deceived.