The Brass Plates Will Retain Their Brightness and Eventually Go Forth to All Nations
3 And these plates of brass, which contain these engravings, which have the records of the holy scriptures upon them, which have the genealogy of our forefathers, even from the beginning—
4 Behold, it has been prophesied by our fathers, that they should be kept and handed down from one generation to another, and be kept and preserved by the hand of the Lord until they should go forth unto every nation, kindred, tongue, and people, that they shall know of the mysteries contained thereon.
5 And now behold, if they are kept they must retain their brightness; yea, and they will retain their brightness; yea, and also shall all the plates which do contain that which is holy writ.
Elder Bruce R. McConkie wrote:
“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 1:14–18).
“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).”
(Mormon Doctrine, 2nd ed. , 103.)