John 1:9 “If we confess our sin, He is faithful and just to forgive us our sin, and to cleanse us from all unrighteousness.”
Have mercy upon me, O God, according to your loving kindness: according to the multitude of your tender mercies blot out my transgressions. Wash me thoroughly from my iniquity, and cleanse me from my sin. For I acknowledge my transgressions: and my sin is ever before me.

Against you, you only, I have sinned and done what is evil in your sight, so that you are justified when you speak and blameless when you judge.

Behold you desire truth in the innermost being, and in the hidden part you will make me know wisdom.
Purge me with hyssop and I shall be clean; wash me and I shall be whiter than snow through Christ who died for my sin.

Amen.