When Saul came back from fighting the Philistines, he was told that David was in the wilderness near Engedi.
Saul took three thousand of the best soldiers in Israel and went looking for David and his men east of Wild Goat Rocks.
He came to a cave close to some sheep pens by the road and went in to relieve himself. It happened to be the very cave in which David and his men were hiding far back in the cave. 1
References for 1 Samuel 24:3
They said to him, "This is your chance! The Lord has told you that he would put your enemy in your power and you could do to him whatever you wanted to." David crept over and cut off a piece of Saul's robe without Saul's knowing it.
But then David's conscience began to hurt,
and he said to his men, "May the Lord keep me from doing any harm to my master, whom the Lord chose as king! I must not harm him in the least, because he is the king chosen by the Lord!" 2
References for 1 Samuel 24:6
So David convinced his men that they should not attack Saul. Saul got up, left the cave, and started away.
Then David went out after him and called to him, "Your Majesty!" Saul turned around, and David bowed down to the ground in respect
and said, "Why do you listen to people who say that I am trying to harm you?
You can see for yourself that just now in the cave the Lord put you in my power. Some of my men told me to kill you, but I felt sorry for you and said that I would not harm you in the least, because you are the one whom the Lord chose to be king.
Look, my father, look at the piece of your robe I am holding! I could have killed you, but instead I only cut this off. This should convince you that I have no thought of rebelling against you or of harming you. You are hunting me down to kill me, even though I have not done you any wrong.
May the Lord judge which one of us is wrong! May he punish you for your action against me, for I will not harm you in the least.
You know the old saying, "Evil is done only by evil people.' And so I will not harm you.
Look at what the king of Israel is trying to kill! Look at what he is chasing! A dead dog, a flea! 3
References for 1 Samuel 24:14
The Lord will judge, and he will decide which one of us is wrong. May he look into the matter, defend me, and save me from you."
When David had finished speaking, Saul said, "Is that really you, David my son?" And he started crying.
Then he said to David, "You are right, and I am wrong. You have been so good to me, while I have done such wrong to you!
Today you have shown how good you are to me, because you did not kill me, even though the Lord put me in your power.
How often does someone catch an enemy and then let him get away unharmed? The Lord bless you for what you have done to me today!
Now I am sure that you will be king of Israel and that the kingdom will continue under your rule.
But promise me in the Lord's name that you will spare my descendants, so that my name and my family's name will not be completely forgotten."
David promised that he would. Then Saul went back home, and David and his men went back to their hiding place.