One simple thing would make me a believer, and of the most ardent type. Have the bible come from many different geographical places around Earth--and all dating from the same time frame.
There are no autographs (original first manuscripts) of any holy book. Even the Gilgamesh tales in Ashurbanipal's library were excellent copies from 1000 years earlier (Hammurabi's library). Autographs are usually accidentally preserved ordinary documents ... "Uzalu orders 3 bushels of barley from the Ur temple". They had no reason to copy or save those in the first place. The first case of preservation of copies of holy books were Babylonians keeping copies of Sumerian holy books, in the original language, because they were still reciting that (with Babylonian accents). One exception, Sumerian or Babylonian kings would put a special tablet in the foundation of a new or rebuilt temple, so that they could brag to future generations. Those are original and not ordinary documents, but of banal content anyway. We did the same at my HS, we put stuff from 1973 in a time capsule under the flag stand.
