The sacrifices of God are a broken spirit, a broken and a contrite heart. Psalms 51:17
David loved the Lord so much and had made many sacrificial offerings to Him, but he realized that God is not pleased by the blood of bulls and goats. David knew that God is pleased by the heart that was broken before for him. Contrite means feeling of guilt because of our wrongdoing and seeking repentance for our sin.
David knew he was a sinner and he prayed that God would create in him a clean heart and renew a steadfast spirit within him. David knew his fellowship with the Lord was broken because of his own sin. He knew that only God could cleanse him. When David recognized his own lustful sin, he offered his own sacrifice of a broken spirit and a contrite heart. Like David, we too must approach God with a broken and a contrite heart because such sacrifice is pleasing and acceptable to our God.