In the book of Mosiah, King Benjamin teaches his sons that their religion and civilization have been preserved only because of the records kept on the plates of brass. he urges them to "remember that were it not for these plates. . . .we must have suffered in ignorance. . .not knowing the mysteries of God." (Mos. 1:3.)
Indeed, the brass plates form the very foundation of the culture of the Book of Mormon peoples, for with them, the Nephites were able to preserve their language (1 Ne. 3:19), their civilization and the religious knowledge of the people from whence they came. (1 Ne. 22:30.)By way of contrast, scholars point out, the Mulekites soon dwindled in apostasy without any records. (Omni 14-18.) "They had lost their knowledge of the gospel because they hand't brought any records with them," said Edward J. Brandt, an LDS author and lecturer on the Old Testament. "That indicates just how vital that foundation [the brass plates] is. As Nephi said [upon slaying Laban in order to obtain the plates], `It is better that one man should perish than that a nation should dwindle and perish in unbelief.' (1 Ne. 4:13.)" Brought by Lehi's people from Jerusalem in 600 B.C., the brass plates contained "the five books of Moses. . . .And also a record of the Jews from the beginning. . . .And also the prophecies of the holy prophets." (1 Ne. 5:11-13.)
Lehi prophesied that the plates, which were handed down through generations from prophet to prophet, "should go forth unto all nations, kindreds, tongues, and people who were of his seed," and that they should "never perish." (1 Ne. 5:18.)
But today's Bible, said Brandt, is only a small portion of what the Nephites originally had on their brass records.
"The plates were much more complete than what we have today," he said. "In 1 Ne. 13:23, reference is made to today's record of the Jews and the relation to what the Nephites had: `It [the Bible] is a record like unto the engravings which are upon the plate of brass, save there are not so many. . . .' "Old Testament prophets," he continued, "were cited by almost all Book of Mormon prophets, and they taught those principles to their families. [The brass plates] became their teaching tool."
Monte S. Nyman, a professor of ancient scripture at BYU, emphasized the extent to which such old world prophets were quoted by Book of Mormon prophets, at a Church Educational System symposium at BYU in October 1979.
"The Book of Mormon mentions Isaiah, Jeremiah, and Malachi by name," Nyman said, "and also affirms several things about the writings of other prophets. . . .
"The Book of Mormon has come forth to bear testimony that the accounts recorded in the Bible were actual events. . . .In so doing, the doctrines of the gospel of Jesus Christ are firmly re-established in our day." That the Book of Mormon is indeed one of the greatest supporters of and commentaries on the Old Testament has been noted by many LDS scholars.
In the same 1979 symposium, President Marion G. Romney observed that "one of the clearest explanations of the Old Testament's great message is contained in [Lehi and Nephi's] writings as found in the Book of Mormon."
Ellis Rasmussen, a renowned Old Testament scholar and former BYU professor, finds that in addition to having "the benefit of seomthing close to the original version of Isaiah and other Old Testament quotations," another value of the brass plates is that they set the precedent for the Nephites' own records.
"It's interesting to consider the possibility that the Book of Mormon plates were patterned after the brass plates," he said. "The idea of record-keeping [was borrowed], and Moroni's comments in Ether 13 indicate that the literary language the Book of Mormon people used for keeping records was the language of the brass plates."
But the intrinsic worth of the plates is to be largely found in the prophetic messages penned by the forebears of the Nephites and Lamanites, writings so essential to their salvation that they might have perished spiritually without them.
"It was the recognition of the importance of the teachings of the Old Testament," President Romney said, "that caused the Lord to inspire Lehi to send his sons back to Jerusalem to get the brass plates. . . .And it was of such great importance that he did not want this new race he was going to raise up from the seed of Lehi to be without it."