When we sin our natural reaction can be to try to hide away from God. Just like Adam and Eve in the garden, we want to cover up our mistakes. David in this Psalm does just the opposite, he brings his brokenness to the Lord and asks God to clean his heart and renew his spirit so his relationship with God would be restored.
Have mercy on me, O God, because of your unfailing love. Because of your great compassion, blot out the stain of my sins.
~ Psalm 51:1 [NLT]