Nephi did not make the small plates until 30 years after Lehi’s colony left Jerusalem (see 2 Nephi 5:28–31). He did not understand why he was commanded to make a second set of records, but he had faith that it was “for a wise purpose” in the Lord (1 Nephi 9:5). Nearly 1,000 years later the prophet Mormon echoed similar words to Nephi’s when he testified that in addition to his abridgment of the large plates of Nephi he was including the small plates of Nephi “for a wise purpose” (Words of Mormon 1:7).
Joseph Smith started the translation of the Book of Mormon with Mormon’s abridgment of the large plates of Nephi. He had completed 116 manuscript pages when Martin Harris pleaded with Joseph to let him take the manuscript and show it to family members. Joseph asked God three different times if Martin could take the manuscript, and permission was finally given. The manuscript fell into the hands of wicked men (see D&C 10:8) and became known as the lost manuscript, or the lost 116 pages.
The loss of the manuscript clearly demonstrates why the Lord commanded Nephi to write the small plates and why Mormon was inspired to include them. Joseph Smith was told not to retranslate the portion he had already completed, but to replace it by translating the small plates of Nephi (see D&C 10:30, 38–45). The translation of the 116 pages covered 600–130 B.C.—from the time of Lehi to the time of King Benjamin. The small plates also covered 600–130 B.C.— from Lehi to King Benjamin. The Lord in His omniscience had the second record, the small plates, cover the exact time period that was covered in the stolen 116 pages. This also allowed the Lord to keep His covenant with Enos that “he would preserve the records” (Enos 1:16).
Elder Jeffrey R. Holland of the Quorum of the Twelve Apostles affirmed that the portion of the Book of Mormon that comes from the small plates provides more information than was lost on the 116 pages:
“At least six times in the Book of Mormon the phrase ‘for a wise purpose’ is used in reference to the making, writing, and preserving of the small plates of Nephi (see 1 Nephi 9:5; Words of Mormon 1:7; Alma 37:2, 12, 14, 18). You and I know the wise purpose—the most obvious one—was to compensate for the loss of the earlier mentioned 116 pages of manuscript.
“But it strikes me that there is a wiser purpose than that. … The key to such a suggestion of a wiser purpose is in verse 45 of Doctrine and Covenants section 10. As the Lord instructs Joseph … he says, ‘Behold, there are many things engraven upon the [small] plates of Nephi which do throw greater views upon my gospel’ (emphasis added).
“So, clearly, this was not … tit for tat, this for that—you give me 116 pages of manuscript and I’ll give you 142 pages of printed text. Not so. We got back more than we lost. And it was known from the beginning that it would be so. It was for a wiser purpose. We do not know exactly what we missed in the 116 pages, but we do know that what we received on the small plates was the personal declarations of three great witnesses [Nephi, Jacob, and Isaiah], three of the great doctrinal voices of the Book of Mormon, testifying that Jesus is the Christ. …
“In fact, I think you could make a pretty obvious case that the sole purpose of the small plates was to give a platform for these three witnesses” (“A Standard unto My People” [Church Educational System symposium on the Book of Mormon, Aug. 9, 1994], 9–10; see LDS.org under gospel library/additional addresses/CES addresses).
Elder Neal A. Maxwell testified of the foreknowledge of God and how it builds our faith in Him:
“Few doctrines, save those pertaining to the reality of the existence of God, are more basic than the truth that God is omniscient. …
“… God is perfect in the attributes of divinity, and one of these is knowledge: ‘… seeing that without the knowledge of all things, God would not be able to save any portion of his creatures; for it is by reason of the knowledge which he has of all things, from the beginning to the end, that enables him to give that understanding to his creatures by which they are made partakers of eternal life; and if it were not for the idea existing in the minds of men that God had all knowledge it would be impossible for them to exercise faith in him.’ (Lecture 4, paragraph 11.) …
“God, who knows the beginning from the end, knows, therefore, all that is in between” (All These Things Shall Give Thee Experience [1979], 6–7).