Textual: Ludlow suggests that verse 17 is a Book of Mormon addition to Isaiah (Ludlow 1982, p. 273). While this is a possibility, the verses that follow do not fit into Isaiah, but rather into a specific prophecy to Nephi. Rather than see the “thus saith the Lord God” as an addition to the Isaianic text, it should be seen as Nephi’s declaration of his authority in altering the context of Isaiah’s words. Thus Nephi uses Isaiah’s language as a touchstone, but completes the vision with a prophetic statement declaring the real authority behind Nephi’s vision of the future.
Narrative: Even in this new declaration there is a recasting of Isaiah’s language from chapter 29:11. Nephi references the “sealed book.” At this point in Nephi’s future history he is content to simply link the sealed book to the voice “from the dust.” He will later use more of Isaiah’s passage in his future history, but at this juncture he is content to simply make the connection between his prophecy that “the words of the righteous shall be written, and the prayers of the faithful shall be heard, and all those who have dwindled in unbelief shall not be forgotten” (verse 15).