“By the time of the fall of Babylon in 539 B.C., and the return of the Jewish exiles to Palestine, the core of the Hebrew Bible was completed. The very language of Scripture changed as society became more textualized. Most tellingly, the Hebrew word torah, which originally meant "teaching, instruction," increasingly began to refer to a written text, "the Torah of Moses," (also known as the Pentateuch) in the Second Temple period (530 B.C.–A.D. 130).”
Is this a credible source or not an credible source?