All humans sin. God knew when He created us that we would not be perfect. Even with our best intentions we still sin. Only God has the authority to forgive sins. God loves us so much that he sent Jesus, his only son, to walk the earth and make the perfect sacrifice so that we can be forgiven of our sins. Jesus had the power to overcome death and rise from the grave. That same power can defeat the sins that keep defeating us. By giving our lives to Jesus, and granting him all power over us, we are given victory over our sin.
If we claim that we’re free of sin, we’re only fooling ourselves. A claim like that is errant nonsense. On the other hand, if we admit our sins—make a clean breast of them—he won’t let us down; he’ll be true to himself. He’ll forgive our sins and purge us of all wrongdoing. If we claim that we’ve never sinned, we out-and-out contradict God—make a liar out of him. A claim like that only shows off our ignorance of God.
1 John 1:8-10 (MSG)