2 Kings 8:15
And it came to pass on the morrow, that he took a thick cloth, and dipped it in water, and spread it on his face, so that he died: and Hazael reigned in his stead.
Cross-reference
In 2 Kings 8:13, Hazael scoffs at Elisha's prophecy — now he fulfills it by murdering the king.
In 2 Kings 8:10, Elisha prophesied Ben-Hadad would recover but die — Hazael fulfills that here by smothering him.
1 Samuel 24:4-7 shows David sparing the Lord's anointed — contrasting Hazael's murder of Ben-Hadad.
In 1 Samuel 24:13, David says wickedness comes from the wicked — Hazael's murder exemplifies that, but David refrains.
1 Samuel 26:9-11 asks who can harm the Lord's anointed — Hazael's act is the opposite of David's restraint.
1 Kings 19:15 records God's command to anoint Hazael as king over Syria — this murder fulfills that prophetic commission.
Micah 2:1 condemns devising evil on beds and executing it — exactly what Hazael does to the bedridden king.