16 For thou desirest not sacrifice; else would I give it: thou delightest not in burnt offering.
17 The sacrifices of God are a broken spirit: a broken and a contrite heart, O God, thou wilt not despise.
The blessing of repentance is sweet, but it requires our heart. After David took Bathsheba and killed Uriah, Nathan called him out. Psalm 51 is his humble, penitent reply.
He acknowledged that if repentance were as easy as offering an animal sacrifice, he would gladly do it. But the Lord doesn’t want that outward show of repentance. He wants the sacrifice of our hearts. That requires turning to Him and away from sin. It requires deep commitment, sorrow for our sin, and yielding. It is a lifelong pursuit. But it’s the only thing that allows us the sweetness of repentance.
THIS is the greatest lesson in mortality. True repentance requires our heart. When we give it, we can be cleansed through the power of the Savior’s Atonement.