1 Samuel 26:15-16

David said to Abner, “Are you not a [brave] man? Who is like you in Israel? Why then have you not guarded your lord the king? For one of the people came [into your camp] to kill the king your lord. This thing that you have done is not good. As the LORD lives, you surely deserve to die, because you have not guarded your lord, the LORD’S anointed. And now, see where the king’s spear is, and the jug of water that was by his head.”