1 John 2:1-4

My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous:

And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.

And hereby we do know that we know him, if we keep his commandments.

He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.