1 Samuel 26:6-11, 17-23

Then answered David and said to Ahimelech the Hittite, and to Abishai the son of Zeruiah, brother to Joab, saying, Who will go down with me to Saul to the camp? And Abishai said, I will go down with thee. So David and Abishai came to the people by night: and, behold, Saul lay sleeping within the trench, and his spear stuck in the ground at his bolster: but Abner and the people lay round about him. 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? David said furthermore, As the LORD liveth, the LORD shall smite him; or his day shall come to die; or he shall descend into battle, and perish. The LORD forbid that I should stretch forth mine hand against the LORD's anointed: but, I pray thee, take thou now the spear that is at his bolster, and the cruse of water, and let us go.

And Saul knew David's voice, and said, Is this thy voice, my son David? And David said, It is my voice, my lord, O king. And he said, Wherefore doth my lord thus pursue after his servant? for what have I done? or what evil is in mine hand? Now therefore, I pray thee, let my lord the king hear the words of his servant. If the LORD have stirred thee up against me, let him accept an offering: but if they be the children of men, cursed be they before the LORD; for they have driven me out this day from abiding in the inheritance of the LORD, saying, Go, serve other gods. Now therefore, let not my blood fall to the earth before the face of the LORD: for the king of Israel is come out to seek a flea, as when one doth hunt a partridge in the mountains. Then said Saul, I have sinned: return, my son David: for I will no more do thee harm, because my soul was precious in thine eyes this day: behold, I have played the fool, and have erred exceedingly. And David answered and said, Behold the king's spear! and let one of the young men come over and fetch it. The LORD render to every man his righteousness and his faithfulness: for the LORD delivered thee into my hand to day, but I would not stretch forth mine hand against the LORD's anointed.