1 Samuel 19:24

And he stripped off his clothes also, either by removing all his clothes or at least his outer garment, leaving only the inner shirt of linen or cotton, and prophesied before Samuel in like manner, and lay down, literally, "fell," naked all that day and all that night. The length and the vehemence of the attack of ecstasy which Saul experienced was to indicate to him and others that his persecution of David was a battling against Jehovah and His Spirit, which should therefore not be persisted in, lest more serious effects follow. Wherefore they say, Is Saul also among the prophets? The proverbial saying, which had first gone the rounds when Saul returned from Ramah after meeting Samuel, was now given new nourishment. Unfortunately the heart of Saul remained unchanged, just as the hearts and minds of unbelievers in our days are sometimes drawn into a wave of religious excitement, without a subsequent change of life. Nevertheless, God has even the hearts of His enemies in His power, and they sometimes confess the truth against their will, thus serving the interests of the Lord's kingdom.