David said this prayer asking for repentance after his shameful treatment of Uriah and Bathsheba. This is a helpful prayer of confession and forgiveness for when you feel you have sinned and roamed from the Lord. It is powerful in that you are asking God for Him to help you obey Him. It takes a humble person to ask the Lord for help and forgiveness. We all make mistakes and fall under the spell of evil, so use this prayer when you are ready to apologize for your wrongdoings.
Purify me from my sins, and I will be clean wash me, and I will be whiter than snow…Create in me a clean heart, O God, Renew a loyal spirit within me. Do not banish me from Your presence, and don’t take Your Holy Spirit from me. Restore to me the joy of Your salvation, and make me willing to obey You. (Psalm 51:7, 10-12)