1 John 1:6-9

So we are lying if we say we have fellowship with God but go on living in spiritual darkness; we are not practicing the truth. But if we are living in the light, as God is in the light, then we have fellowship with each other, and the blood of Jesus, his Son, cleanses us from all sin. If we claim we have no sin, we are only fooling ourselves and not living in the truth. But if we confess our sins to him, he is faithful and just to forgive us our sins and to cleanse us from all wickedness.