1 Samuel 19:24

And he stripped off his clothes also, and prophesied before Samuel in like manner, and lay down naked all that day and all that night. Wherefore they say, Is Saul also among the prophets?

Saul came to Ramah to Samuel's home among the school and company of the prophets where Samuel was, while he was hunting and pursuing David in search of him and seeking to capture him. He arrived with an envious and jealous spirit and with hostility toward David. In stripping off his clothes he laid aside the outer garments that marked his royal rank, and he lay under the influence of God's Spirit all that day and all that night.

The Spirit of God was so manifest in that place that it came upon Saul, and hearing the prophets stirred him to forget his pursuit and to prophesy before Samuel together with the prophets, joining them in praise as his messengers had done. The school of the prophets where this happened trained people in the Scriptures and in praise to God, and prepared them to receive the endowment of the Holy Spirit and then to carry their testimony to others into places where people needed to hear it. Those prophets prayed until the Holy Spirit rested on them and then communicated the light God had given them, showing how manifest the Spirit was in the school.

Saul's surprising change became widely known and gave rise to and renewed the common saying about Saul being also among the prophets, showing the Spirit's power to move even someone who came with a hostile disposition to praise God. While under this influence Saul had a different spirit and was temporarily turned from his hostility so that he failed to capture David, who still had to hide, but the influence did not last. Saul did not continue under the Spirit's influence but lost it and again sought David's life; had he continued he would have been in an excellent condition, so the episode does not show the enduring work needed to form a character fit for immortal life.