10 When they were going from there to Gibeah, a band of prophets met him; and the spirit of God possessed him, and he fell into a prophetic frenzy along with them. 11 When all who knew him before saw how he prophesied with the prophets, the people said to one another, "What has come over the son of Kish? Is Saul also among the prophets?" 12 A man of the place answered, "And who is their father?" Therefore it became a proverb, "Is Saul also among the prophets?"
Matthew Henry's Commentary on 1 Samuel 10:10-12
Commentary on 1 Samuel 10:9-16
(Read 1 Samuel 10:9-16)
The signs Samuel had given Saul, came to pass punctually; he found that God had given him another heart, another disposition of mind. Yet let not an outward show of devotion, and a sudden change for the present, be too much relied on; Saul among the prophets was Saul still. His being anointed was kept private. He leaves it to God to carry on his own work by Samuel, and sits still, to see how the matter will fall.