David Seely notes that King Josiah (640-609 B.C.) was a contemporary of Lehi. In the course of Josiah's religious reforms, a book was discovered in the temple that many scholars believe was some form of the book of Deuteronomy. Josiah's reforms are described in language similar to that in Deuteronomy, and the nature of the reforms closely follows the laws found only in Deuteronomy. These reforms are significant for Book of Mormon studies since Lehi grew up in Jerusalem during the reign of Josiah and must have been influenced by the religious reforms that affected the lives of everyone living there.
According to Seely, in recounting the history of his father's exodus some thirty to forty years after the fact, Nephi was undoubtedly influenced by the scriptures contained on the brass plates, which contained the five books of Moses--and thus the book of Deuteronomy (see 1 Nephi 5:11). The language and theology of the Book of Mormon seem heavily dependent on Deuteronomy, perhaps more than any other biblical book. The very basis of the oft-repeated covenant in the Book of Mormon that "inasmuch as ye shall keep my commandments, ye shall prosper" (1 Nephi 2:20) reflects the theology of Deuteronomy: "Keep therefore the words of this covenant, and do them, that ye may prosper in all that ye do" (Deuteronomy 29:9). [David R. Seely, "Lehi's Altar and Sacrifice in the Wilderness," in Journal of Book of Mormon Studies , vol. 10, num. 1, 2001, p. 67] [See Vol. 6, Appendix C]