1 John 2:1-6 NIV
My dear children, I write this to you so that you will not sin. But if anybody does sin, we have an advocate with the Father—Jesus Christ, the Righteous One. He is the atoning sacrifice for our sins, and not only for ours but also for the sins of the whole world.
We know that we have come to know him if we keep his commands. Whoever says, “I know him,” but does not do what he commands is a liar, and the truth is not in that person. But if anyone obeys his word, love for God is truly made complete in them. This is how we know we are in him: Whoever claims to live in him must live as Jesus did.
NIV: New International Version