All things bear record · 2 Samuel
3 witnesses of Christ here, and 1 further echo from the reading.
And the LORD sent Nathan unto David. And he came unto him, and said unto him, There were two men in one city; the one rich, and the other poor. 2 Samuel 12:1
Jehovah does not leave David in his sin but sends a prophet to bring him to repentance.
How we know: Jehovah is the premortal Christ (Abraham 1:16; D&C 110:3–4)
And Nathan said to David, Thou art the man. Thus saith the LORD God of Israel, I anointed thee king over Israel, and I delivered thee out of the hand of Saul; 2 Samuel 12:7–12
Through Nathan, Jehovah speaks in the first person: He anointed David, gave him everything, and now pronounces the consequences of his sin. The premortal Christ is the God of Israel who both blesses and judges His covenant king.
How we know: Jehovah is the premortal Christ (Abraham 1:16; D&C 110:3–4)
And David said unto Nathan, I have sinned against the LORD. And Nathan said unto David, The LORD also hath put away thy sin; thou shalt not die. 2 Samuel 12:13–14
David confesses that his sin was against the LORD, and only the LORD can deal with it. Latter-day revelation teaches that David's sin in Uriah's death was grave enough that he lost his exaltation (D&C 132:39), so this verse is about Jehovah sparing his mortal life, not full forgiveness; it still shows that sin is answered to Jehovah, the Redeemer.
How we know: Jehovah is the premortal Christ (Abraham 1:16; D&C 110:3–4)
Jedidiah — beloved of the LORD (Jehovah)
And David comforted Bathsheba his wife, and went in unto her, and lay with her: and she bare a son, and he called his name Solomon: and the LORD loved him. 2 Samuel 12:24–25
Solomon, the heir through whom the Davidic promise of chapter 7 continues, is named 'beloved of the LORD.' He foreshadows the true Son of David whom the Father would call 'my beloved Son.'