Voices from Out of the Dust

Church Educational System
Nephi is evidently quoting from a statement found in Isaiah 29:4 when he refers to a destroyed people whose record shall come ‘out of the ground, and their speech shall be low out of the dust, and their voice shall be as one that hath a familiar spirit.’ (2 Nephi 26:16.) …

… A careful reading of this scripture, particularly when read together with Nephi’s explanation, would indicate that the term it ‘hath a familiar spirit’ means that this record (the Book of Mormon) would speak with a ‘familiar voice’ to those who already have the Bible. In other words, Nephi is evidently saying here that the doctrinal teachings of the Book of Mormon would seem familiar to people who had already read and accepted the Bible.

(Daniel H. Ludlow, A Companion to Your Study of the Book of Mormon, p. 146)

Book of Mormon Student Manual (1996 Edition)