I suspect that the narrative of Samuel has much to teach us about the character of God: observe that David and Saul are both portrayed as rebellious men who break God’s word and law. David is still portrayed as a man after God’s own heart, yes, but these are glimmers of light in the midst of pressing darkness: David shows true penitence, but only after he is confronted by Nathan—months after adultery and murder. David sings of God’s great acts (2 Sam. 24), but only after he allows his sons to murder one another, descend into rebellion, and after he almost loses the Kingdom to an apostate son on account of his failure to act (2 Sam. 15-18). Saul is bad, yes, but so is David. David is better—a bit—but the narrator draws attention to something else that differentiates them. For the author of Samuel, David’s character is not the primary thing that separates him from Saul: for the author of Samuel, God’s election and mercy separates David from Saul. Saul was the king the people wanted; God chose him, but He chose him on their terms. David was the king God wanted. The theme of Samuel is the raising of the lowly and the shattering of the strong (1 Sam. 2:7-8): Saul is tall, from the city called “hill” and continues to live in the “hill of Saul” (9:2, 10:26, 11:4).1 David is a lowly shepherd, who is appointed to shepherd God’s people Israel. David gets power, and begins to abuse it—taking more and more wives is not a sign of blessing (cf. Deut. 17:17)—finally committing adultery and murder, and neglecting the kingdom.
Yet, despite the failures of David, God’s promises remain. It is true that when Saul sins, his answer is full of excuses, yet he still admits he sinned (by listening to the people) and asks that his sins be forgiven (1 Sam. 15:24). Yet, God tells Saul that he will take away his kingdom. David, on the other hand, receives his indictment not immediately (as with Saul) but after a lengthy wait of more than 9 months (the child is born by this time): in all this time, he did not repent. At Nathan’s words, he does indeed confess his sin: “I have sinned against YHWH.” Nathan then gives the positive verdict: “God has even forgiven your sin; you will not die.” David’s house will face horrible consequences, yet it will not be cut off: whereas God took the kingdom of Saul and gave it to his “neighbour” (1 Sam. 15:28), here YHWH will give David’s wives to a “neighbour” and he will sleep with them in broad daylight (2 Sam. 12:11). God calls David “better” than Saul (1 Sam. 15:28), but it becomes clear throughout the narrative that David is not king and does not receive the promise of a kingdom on account of his righteousness; David receives the kingdom on account of grace, God stooping to exalt the lowly and use the unexpected for His purposes.
David will become the poster boy of a faithful king in the book of Kings, and Chronicles highlights his penitence and faithfulness to YHWH; the Psalms, also, present David as an imperfect man dedicated to YHWH. These are necessary and helpful representations of David, the historical king of Israel, yet these are not Samuel’s portrayal. The books of Samuel represent David at his best initialy—in contrast to Saul—but then more and more at his worst. Samuel wants us to see that God’s purposes are not going to be fulfilled on the initiative or greatness of a human being but only by the sovereign election and mercy of the YHWH—the sovereign ruler of the heavens and the earth:
The Lord kills and brings to life;
he brings down to Sheol and raises up.
The Lord makes poor and makes rich;
he brings low and he exalts.
He raises up the poor from the dust;
he lifts the needy from the ash heap
to make them sit with princes
and inherit a seat of honor.
For the pillars of the earth are the Lord’s,
and on them he has set the world.
He will guard the feet of his faithful ones,
but the wicked shall be cut off in darkness,
for not by might shall a man prevail.
The adversaries of the Lord shall be broken to pieces;
against them he will thunder in heaven.
The Lord will judge the ends of the earth;
he will give strength to his king
and exalt the horn of his anointed.” (1 Sam. 2:6-10, ESV)