en_tn_lite_do_not_use/act/26/22.md

to both small and great about nothing

Here "small" and "great" refer to people who are unimportant and important, respectively, and are used together to mean "all people." Alternate translation: "to all people, whether unimportant or important, about nothing" (See: rc://en/ta/man/jit/figs-merism)

about nothing more than what

This can be stated in positive form. Alternate translation: "about the exact thing that"

what the prophets

Paul is referring to the collective writings of the Old Testament prophets.