There were three … witnesses—special witnesses—not only of the divine origins of the Book of Mormon but also of Divinity himself. These early witnesses were Nephi, Jacob, and Isaiah, and it is not by coincidence that their testimonies appear so conspicuously at the beginning of this ancient record… .
The “greater views” of the gospel found in the teachings of the small plates of Nephi come from the personal declarations of these three great prophetic witnesses of the premortal Jesus Christ—Nephi, Jacob, and Isaiah. These three doctrinal and visionary voices make clear at the very outset of the Book of Mormon why it is “another testament of Jesus Christ.”
In declaring the special preparation these three had for receiving and teaching such “greater views” of the gospel, Nephi revealed the most persuasive qualification of all: They had seen the premortal Jesus Christ (2 Ne. 11:2–3).
One could argue convincingly that the primary purpose for recording, preserving, and then translating the small plates of Nephi was to bring forth to the dispensation of the fulness of times the testimony of these three witnesses. Their writings constitute a full 135 of the 145 pages from the small plates… . After reading these three witnesses from the small plates of Nephi, the reader knows two things in bold relief: that Jesus is the Christ, the Son of the Living God, and that God will keep his covenants and promises with the remnants of the house of Israel. Those two themes constitute the two principal purposes of the Book of Mormon, and they are precisely the introductory themes addressed by Nephi, Jacob, and Isaiah.
(Jeffrey R. Holland, Christ and the New Covenant [Salt Lake City: Deseret Book Co., 1997], 34–35.)