The contents of the plates of brass as described by Alma (v. 3) is very general when compared to Lehi’s description in 1 Nephi 5:11–14. Undoubtedly Helaman was already familiar with them so Alma was brief. The prophecy of the brass plates going to every nation, tongue, and people (v. 4) is yet to be fulfilled. Its fulfillment will probably be millennial, but at least will be after the plates are brought again to the earth, translated and made known to the people. They are still in existence because they were shown to Joseph Smith, Oliver Cowdery, and others at the Hill Cumorah. When they are brought forth they will verify that many plain and precious things have been lost from the Old Testament (see 1 Nephi 13:26–29). The Book of Mormon has given many people a knowledge of many things that were lost, and the plates of brass will verify the Book of Mormon accounts and show us many more.
The second prophecy, that the plates would retain their brightness (Alma 37:5), was made nearly twenty-one hundred years ago, and the plates had already been with the Nephites for over five hundred years. How old they were at that time we do not know, but in round numbers it could be at least three thousand years old. Such preservation would certainly require the hand of the Lord. Father Lehi made these two prophecies when he first examined them in the valley of Lemuel after his sons had brought them from Jerusalem (1 Nephi 5:18–19). Alma adds that all plates that contain holy writ will likewise be preserved. Thus we can look forward to seeing and learning from many metallic plates. Joseph and Oliver and their company were shown wagon loads of plates when they were at the Hill Cumorah as mentioned above (see footnote 4).
The phrase “small means in many instances doth confound the wise” (Alma 37:6) is a comparison to other means that are used, as measured by the world’s standards. Nephi made a similar statement about the ball or director (see 1 Nephi 16:28–29). By a process, small to the Lord, but larger than man can understand, the Lord had done something to those sacred plates to preserve them beyond the capacity of man. The purpose in doing so was to bring about the eternal purposes of saving souls (Alma 37:7). God’s “work and [his] glory [is] to bring to pass the immortality and eternal life of man” (Moses 1:39). The plates of brass contain writings that revealed the eternal plan of God to save souls. The ball or director was to direct the Lord’s chosen to his promised land that many souls would be saved. It was a means to receive revelation (see 1 Nephi 16:28–29). These eternal means are small to the world, but enormous to those who are spiritually hungry.
As evidence of what the plates of brass could do in the future, Alma cites what they had already done among the people of Lehi. The memory of the Nephites had been enlarged, and brought them to the knowledge of God (Alma 37:8). In over five hundred years (600 to 74 B.C.) the numbers that plates have influenced would be impossible to count. In addition, the Lamanite converts, through the help of the plates of brass, were many thousands (v. 9). Projecting into the future, Alma sees many more thousands of Lamanites and Nephites coming to the knowledge of their Redeemer, but he is reticent to predict (v. 11). Parenthetically, this verse is a good answer to speculative questions on the gospel.
Comparing the book of Mormon, a small means the Lord has provided for our day, to the plates of brass would change the numbers to millions instead of thousands that have come to the knowledge of their Redeemer through that marvelous book. It also was preserved for a wise purpose in the Lord (v. 12; compare Words of Mormon 1:7).