Everyone who knows the Bible knows that King David was a great man.
And yet everyone familiar with the Bible will also recognize that David did a lot of not-so-great things. Of course, there was the sin with Bathsheba, the murder of her husband Uriah, and the subsequent cover-up. That was not exactly delighting in the law of the Lord (Psalm 1:2). But there was also the ill-advised census motivated by David’s pride, not to mention a series of lessons in how not to manage your household well. For being a man after God’s own heart (Acts 13:22), David managed to follow his own heart quite a bit.
So with all these flaws, what made David great? One could easily mention David’s courage, his loyalty, his faith, his success as a leader, musician, and warrior. But he was great in other lesser-known ways as well. In particular, David was a great man because he was willing to overlook others’ sin but unwilling to overlook his own.
David was a gracious man, bearing with the failings of others, eager to give his enemies a second chance. Twice, while his friends advised him to strike down their enemy, David spared Saul’s life, (1 Samuel 24; 26). Though Saul opposed him at every turn, David did not rejoice at his death, but wept for the king and his son Jonathan (2 Sam. 1:17-27). David welcomed Abner when he defected from the phony king Ish-bosheth and mourned for him when distrusting Joab stuck him down (2 Sam. 3). David was unnecessarily kind to Mephiboseth (2 Sam. 9) and uncommonly patient with Shimei’s spiteful cursing. Later David would pardon those who rebelled against him during Absalom’s insurrection (2 Sam. 19:16-23). Time after time David showed himself to be unlike the sons of Zeruiah who lived to hold grudges and settle scores. David knew how to forgive. More than anyone prior to Jesus, David loved his enemies. Like no other Old Testament king, David was willing to welcome rebels back to the fold and overlook the sins of those who had opposed him.
But amazingly, David’s kind-hearted attitude toward his enemies did not translate into a soft attitude toward his own sins. Usually, people who are soft with others are soft with themselves, and those hardest on themselves are even harder on others. But David was different. He was gracious with others and honest with himself. I believe David’s greatness was simply this: for as much as he sinned he never failed to own up to his sin. I can’t find a single instance where David was rightly rebuked for his failings where he then failed to heed the rebuke. When Nathan confronts David for his adultery and murder, David, after he sees what Nathan is up to, quickly laments, “I have sinned against the Lord” (2 Sam. 12:13). When Joab sends the woman of Tekoa to change David’s mind about Absalom, he listens. When Joab rebukes David for loving his treacherous son more than his loyal servants, David does what Joab tells him to do (2 Sam. 19:1-8). Joab was often wrong in his advice to David, but when he was right David saw it and changed course. Likewise, after his foolish census, David’s heart struck him and he confessed, “I have sinned greatly in what I have done” (2 Sam. 24:10).
David knew how to forgive, and he knew how to repent too. He never blamed others for his mistakes. He did not make excuses based on family history, peer pressure, or the demands of leadership. He did not use passive language, referring to his sin as a dysfunction or a growth edge. He did not lament over his sins simply because of the negative effects they could have over his kingdom and his relationships. He saw his transgressions primarily in their vertical dimension, as an offense against almighty God (Psalm 51:4). He never ran from the light when it exposed his darkness. Instead, he squinted hard, admitted his iniquity and worked to make things right. When we consider how rare it is in our day for athletes, movie stars, and politicians to candidly and clearly take responsibility for their public sins, we should be all the more amazed that the king of Israel, arguably the most famous man in the history of God’s old covenant people, was humble enough to listen to the chastisement of those who were beneath him and change accordingly.
David was a man after God’s own heart because he hated sin but loved to forgive it. What better example of God could there be? God doesn’t just welcome his enemies in, he dies in their stead (Rom. 5:6-11). He is always eager to show mercy, always willing to give traitors a second chance. And yet, God is not soft on sin. He exposes it and calls on us to exterminate it (John 16:8-11; Col. 3:5). But of course, God, unlike David, is never guilty of his own sin. God showed his condescension not by humbling himself before a needed rebuke, but by humbling himself to take on human flesh and take up a cross (Phil. 2:5-8). David was great, but not nearly as much as great David’s greater Son.
https://www.thegospelcoalition.org/blogs/kevin-deyoung/what-made-david-great/