“When the Lord led Lehi and his colony out from Jerusalem, they were required to take with them the Brass Plates of which Laban had been the custodian. These plates—which Nephi acquired through his faith, works, and zeal (1 Ne. 3; 4)—were a volume of sacred scripture. They contained a record of God’s dealings with men from the beginning down to that day. They were ‘the record of the Jews’ (1 Ne. 3:3), a record of many of the prophecies from the beginning down to and including part of those spoken by Jeremiah. On them was the law of Moses, the five books of Moses, and the genealogy of the Nephite forbears. (1 Ne. 3:3, 20; 4:15–16; 5:11–14.)
“There was more on them than there is in the Old Testament as we now have it. (1 Ne. 13:23.) The prophecies of Zenock, Neum, Zenos, Joseph the son of Jacob, and probably many other prophets were preserved by them, and many of these writings foretold matters pertaining to the Nephites. (1 Ne. 19:10, 21; 2 Ne. 4:2, 15; 3 Ne. 10:17.)
“The value of the Brass Plates to the Nephites cannot be overestimated. By means of them they were able to preserve the language (1 Ne. 3:19), most of the civilization, and the religious knowledge of the people from whence they came. (1 Ne. 22:30.) By way of contrast, the Mulekites, who were led out of Jerusalem some 11 years after Lehi’s departure, and who had no record equivalent to the Brass Plates, soon dwindled in apostasy and unbelief and lost their language, civilization, and religion. (Omni 14–18.)
“From prophet to prophet and generation to generation the Brass Plates were handed down and preserved by the Nephites. (Mosiah 1:16; 28:20; 3 Ne. 1:2.) At some future date the Lord has promised to bring them forth, undimmed by time and retaining their original brightness, and the scriptural accounts recorded on them are to ‘go forth unto every nation, kindred, tongue, and people.’ (Alma 37:3–5; 1 Ne. 5:18–19.)” (Bruce R. McConkie, Mormon Doctrine, p. 103).
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“There was more on them than there is in the Old Testament as we now have it. (1 Ne. 13:23.) The prophecies of Zenock, Neum, Zenos, Joseph the son of Jacob, and probably many other prophets were preserved by them, and many of these writings foretold matters pertaining to the Nephites. (1 Ne. 19:10, 21; 2 Ne. 4:2, 15; 3 Ne. 10:17.)
“The value of the Brass Plates to the Nephites cannot be overestimated. By means of them they were able to preserve the language (1 Ne. 3:19), most of the civilization, and the religious knowledge of the people from whence they came. (1 Ne. 22:30.) By way of contrast, the Mulekites, who were led out of Jerusalem some 11 years after Lehi’s departure, and who had no record equivalent to the Brass Plates, soon dwindled in apostasy and unbelief and lost their language, civilization, and religion. (Omni 14–18.)
“From prophet to prophet and generation to generation the Brass Plates were handed down and preserved by the Nephites. (Mosiah 1:16; 28:20; 3 Ne. 1:2.) At some future date the Lord has promised to bring them forth, undimmed by time and retaining their original brightness, and the scriptural accounts recorded on them are to ‘go forth unto every nation, kindred, tongue, and people.’ (Alma 37:3–5; 1 Ne. 5:18–19.)” (Bruce R. McConkie, Mormon Doctrine, p. 103).