en_tn_lite_do_not_use/1sa/19/23.md

This is why they ask, "Is Saul also among the prophets?"

This became a proverb among the Israelites. Apparently people said this to express surprise when a person unexpectedly did something that he had not done before. The implied meaning of the question can be stated explicitly. See how you translated this in 1 Samuel 10:12. AT: "That is the reason that when people see someone doing something that is very unexpected, they say, 'Is Saul also a prophet?'" (See: rc://en/ta/man/translate/writing-proverbs and rc://en/ta/man/translate/figs-explicit)

they ask

Here "they" refers to people in general. The question became a proverb among the people.