According to David Seely, readers often ask why Nephi included particular passages from Isaiah in his writings and what message Nephi would have us learn from that passage. Nephi does much to help readers understand the words of Isaiah by answering these questions both directly and indirectly in his introductory statements and through his commentaries. For example, Nephi introduces his quotation of Isaiah 48 and 49 in 1 Nephi 20-21 by indicating that the prophet's words refer to the scattering and gathering of Israel:
Wherefore I spake unto them, saying: Hear ye the words of the prophet [Isaiah], ye who are a remnant of the house of Israel, a branch who have been broken off; hear ye the words of the prophet [Isaiah], which were written unto all the house of Israel, and liken them unto yourselves, that ye may have hope as well as your brethren from whom ye have been broken off; for after this manner has the prophet written. (1 Nephi 19:24)
After quoting Isaiah 48 and 49, Nephi then explains to his brothers Laman and Lemuel that these chapters refer to a temporal as well as a spiritual scattering of Israel, including the scattering and gathering of the Nephite and Lamanite seed (see 1 Nephi 22). [David Rolph Seely, "Nephi's Use of Isaiah 2-14 in 2 Nephi 12-30," in Isaiah in the Book of Mormon, p. 151]