This verse establishes that Nephi omitted a great deal of material from his report of Lehi’s sermon. Almost certainly, Lehi would have named the individual prophets in this “great number” who had predicted the Messiah’s coming—including Isaiah, Zenos, and Zenock—and probably would have quoted at least selected prophecies. Nephi moves over this section of the sermon with the briefest of mentions. This omission tells us more about Nephi’s purposes than it does about Lehi. Such information was simply not important in fulfilling Nephi’s narrative purposes.
Even though Nephi drastically summarizes what must have been Lehi’s record of this sermon, it does not alter or obscure Lehi’s emphasis, since Lehi’s point (to testify of the Messiah and his atonement) is also the point of Nephi’s record.