David the righteous sinner

The other night I listened to a lecture on 1 Chronicles 21 (David's census, God's judgment, and David's repentance) and Psalm 51. The lecturer (Douglas Green, professor in OT at Westminster) argued that both passages are about David's righteousness. Sin is inevitable and David was being the perfect Israelite modeling heart repentance as the law required it.

⁸ Then David said to God, "I have sinned greatly by doing this. Now, I beg you, take away the guilt of your servant. I have done a very foolish thing."

⁹ The LORD said to Gad, David's seer, ¹⁰ "Go and tell David, 'This is what the LORD says: I am giving you three options. Choose one of them for me to carry out against you.' "

¹¹ So Gad went to David and said to him, "This is what the LORD says: 'Take your choice: ¹² three years of famine, three months of being swept away ^a]">[a] before your enemies, with their swords overtaking you, or three days of the sword of the LORD -days of plague in the land, with the angel of the LORD ravaging every part of Israel.' Now then, decide how I should answer the one who sent me."

¹³ David said to Gad, "I am in deep distress. Let me fall into the hands of the LORD, for his mercy is very great; but do not let me fall into the hands of men."

1 Chronicles 21:8-13

An interesting idea. Heartwarming. Anyone come across it before?