It happened, when all who knew him before saw that, behold, he prophesied with the prophets, then the people said one to another, What is this that is come to the son of Kish? Is Saul also among the prophets?
God’s Spirit also gave Saul the ability to prophesy (1 Samuel 10:10). This was the outward evidence that God was with Saul. It apparently involved the Holy Spirit controlling these men, and their manifesting His control by praising God (cf. 1 Samuel 19:20-24; 1 Chronicles 25:1-3). The evidence of this new gift surprised people who knew Saul, and they took note of it (1 Samuel 10:11). Some students of this passage have concluded that Saul demonstrated this gift with ecstatic behavior. [Note: E.g., Bright, p. 166.] Others have not. [Note: E.g. Leon J. Wood, "Ecstasy and Israel’s Early Prophets," Bulletin of the Evangelical Theological Society 9 (Summer 1966):125-37. See also idem, The Prophets . . ., pp. 40-56, 91-92.] I see no evidence of it in the text.