Do you feel guilty or feel bad about something that you've done...thought...said? Ashamed? Full of regret? Have you shared your struggle(s) with anyone?
In Psalm 51, David shares how he felt when he was dramatically confronted with his sins by the propet Nathan (2 Samuel 12:1-25): an extended experience of lust and adultery that led to murder and resulted in tremendous guilt and the loss of his infant son shortly after his birth. In this Psalm, he experiences the fulness and depth of guilt, shame and regret, yet in the very realization of how his sin is not just against Uriah and Bathsheba, his court and his nation, but against God...David experiences the joy of hope in God's forgiveness and ultimate salvation. This Psalm is a great example of why David was known as a man who was "after God's own heart." His example of dealing with his adultery, murder, lying and covering up his sin when confronted is a great example not only of true repentance, but of faith and hope in God's power and will to save. To redeem. To transform us into the people he envisions us to be.
In Luke 18:9-14, Jesus tells a story about two men praying. He highlights the spiritual result of being humble and in touch with one's own sinfulness in a healthy way (c.f., Psalm 51:14-19). Repentance and inward spiritual transformation must occur in order for ritual sacrifices to be meaningful (c.f., Psalm 51:18-21).
Psalm 103 reminds us that the God who made us from dust knows exactly who and what we are. He made us. He knows we are weak and sinful and he loves and forgives us. He is full of compassion and grace. "Merciful and gracious is the LORD, slow to anger, abounding in kindness."
Hebrews 10 explains that Jesus is the ultimate "once and for all" sacrifice that really does take away our sins for good. So "let us consider how we may spur one another on toward love and good deeds, not giving up meeting together, as some are in the habit of doing, but encouraging one another—and all the more as you see the Day approaching."