The sight of Saul suddenly prophesying sparked immediate amazement among the onlookers. Their surprise was rooted in his family background; as the son of Kish, he came from a lineage that seemed entirely disconnected from the spirit of prophecy. To address the confused crowd, a local man from the city of Gibeah steps forward to correct their fundamental misunderstanding about how prophecy works [מצודת דוד].
The man challenges the crowd by asking about the ancestry of the other prophets standing before them. The primary approach among commentators is that he wanted to emphasize that prophecy is not an inherited trait passed down from father to son. Since the ancestors of this band of prophets were not prophets themselves, there was no reason to be shocked that the son of Kish was now prophesying. In the previous generation, the word of God was quite rare. Therefore, these prophets clearly did not inherit their abilities; rather, they actively chose this spiritual path [ביאור שטיינזלץ] or studied and reached perfection under the guidance of Samuel [רלב״ג, מלבי״ם].
Taking a different perspective, another view suggests that the reference to a father in the man's challenge actually means a teacher or master. According to this approach, the local man was pointing out that God is the ultimate teacher who places the spirit of prophecy upon a person. The same God who granted prophetic vision to the rest of the group could easily grant it to Saul as well [רד״ק].
This unexpected event and the local man's intervention gave birth to a famous saying in Israel. The crowd's initial question about Saul being among the prophets evolved into a common proverb used throughout the generations. It became the standard expression for any ordinary person who suddenly rises to greatness, achieving a status they were completely unaccustomed to [רד״ק, מצודת דוד, ביאור שטיינזלץ]. More specifically, it perfectly describes someone who reaches a remarkably high level of achievement without having made any prior preparations for such a role [מלבי״ם].