1 Samuel 24:3-7

And he came to the sheepcotes by the way, where was a cave; and Saul went in to cover his feet. Now David and his men were abiding in the innermost parts of the cave. And the men of David said unto him, Behold, the day of which Jehovah said unto thee, Behold, I will deliver thine enemy into thy hand, and thou shalt do to him as it shall seem good unto thee. Then David arose, and cut off the skirt of Saul’s robe privily. And it came to pass afterward, that David’s heart smote him, because he had cut off Saul’s skirt. And he said unto his men, Jehovah forbid that I should do this thing unto my lord, Jehovah’s anointed, to put forth my hand against him, seeing he is Jehovah’s anointed. So David checked his men with these words, and suffered them not to rise against Saul. And Saul rose up out of the cave, and went on his way.