1 Samuel 26:9-11

9“No!” David said. “Don’t kill him. For who can remain innocent after attacking the Lord’s anointed one?

10Surely the Lord will strike Saul down someday, or he will die of old age or in battle.

11The Lord forbid that I should kill the one he has anointed! But take his spear and that jug of water beside his head, and then let’s get out of here!”