1 John 1:7, 9, and 2:1-2 (NIV)

1:7 – But if we walk in the light, as He is in the light, we have fellowship with one another, and the blood of Jesus, His Son, purifies us from every sin.

1:9 – If we confess our sins, He is faithful and just and will forgive us our sin and purify us from all unrighteousness.

2:1-2 – My dear children, I write this to you so that you will not sin. But if anybody does sin, we have one who speaks to the Father in our defense – 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.