1 Samuel 24:4 - Joseph Benson’s Commentary on the Old and New Testaments

The men of David said unto him, &c. The cave being very large, and David and his men at the further end of it, they might see Saul by the light of the entrance, without his seeing them, and might whisper together what follows without being heard. The Lord said unto thee, Behold, I will deliver, &c. We do not read anywhere that God said these very words, or made a promise to deliver Saul into David's hands. But they put this construction on what Samuel had said about taking the kingdom from Saul and giving it to David, and on those promises which God had made to him of delivering him from all his enemies, and carrying him through all difficulties to the throne. These promises, they conceived, laid him under an obligation of taking all opportunities which God put into his hands for their accomplishment. Add to this, that, having a desire to return to their own habitations, and also to have preferment under David, they wished him to seize this occasion which now presented itself of destroying his enemy, and advancing himself. Then David arose and cut off the skirt of Saul's robe privily Which he might easily do, as he was asleep.