1 Samuel 26:8-9

Then said Abishai to David, God hath delivered thine enemy into thine hand this day: now therefore let me smite him, I pray thee, with the spear even to the earth at once, and I will not smite him the second time. And David said to Abishai, Destroy him not: for who can stretch forth his hand against the LORD's anointed, and be guiltless?