1 Samuel 26:5

Then Saul arose and went down to the wilderness of Ziph, having three thousand chosen men of Israel with him, to seek David in the wilderness of Ziph.

Saul encamped in the hill of Hachilah, which is before the desert, by the way. But David stayed in the wilderness, and he saw that Saul came after him into the wilderness.

David therefore sent out spies, and understood that Saul had certainly come.

Then David answered and said to Ahimelech the Hittite, and to Abishai the son of Zeruiah, brother of Joab, saying, “Who will go down with me to Saul to the camp?”

Abishai said, “I will go down with you.”

So David and Abishai came to the people by night; and, behold, Saul lay sleeping within the place of the wagons, with his spear stuck in the ground at his head; and Abner and the people lay around him.

Then Abishai said to David, “God has delivered up your enemy into your hand today. Now therefore please let me strike him with the spear to the earth at one stroke, and I will not strike him the second time.”