What does Psalm 51:10 mean?

David's heart had been full of lust for Bathsheba, murderous plans for Uriah, and rebellion against God. He desired a new heart, one that was full of love for God and abhorrence of evil. Sin in his heart had brought him nothing but guilt, grief, and remorse. He wanted spiritual heart surgery that only God could perform.

Jesus cited the heart as the source of either good or evil. He explained: "The good person out of the good treasure of his heart produces good, and the evil person out of his evil treasure produces evil, for out of the abundance of the heart his mouth speaks" (Luke 6:45). Jesus also said that "everyone who looks at a woman with lustful intent has already committed adultery with her in his heart" (Matthew 5:28). David, therefore, had committed adultery with Bathsheba in his heart before the physical act of adultery took place. He needed a new heart. But he also asked the Lord to renew a right spirit within him (Psalm 51:10). He wanted the kind of spirit that would obey the Lord at all times.