Why did David emphasize the need for a clean heart?

David's plea for a clean heart in Psalm 51 is significant as it speaks to the necessity of inner transformation for true worship. He understood that external rituals were inadequate without spiritual renewal granted by God. A clean heart symbolizes a restored relationship with the Lord, freed from the guilt and stain of sin. This desire for purity underscores the Reformed understanding that genuine worship must come from a redeemed heart, made new through faith in Christ. David's recognition of his need for cleansing reflects a profound theological truth: our relationship with God hinges on the condition of our hearts rather than mere outward actions.