Adam Clarke on 1 Samuel 19:24

He stripped off his clothes - Threw off his royal robes or military dress, retaining only his tunic; and continued so all that day and all that night, uniting with the sons of the prophets in prayers, singing praises, and other religious exercises, which were unusual to kings and warriors; and this gave rise to the saying, Is Saul also among the prophets? By bringing both him and his men thus under a Divine influence, God prevented them from injuring the person of David. See the notes on 1Sam 10:6 (note), etc.; and see my sermon on The Christian Prophet and his Work.