Ether’s stones are clearly meant to help interpret the writings (the twenty-four gold plates) that Ether is sealing up. Alma 37:21–35 gives additional history about these plates. During this discussion about the twenty-four gold plates, Ammon tells Limhi that Mosiah possesses the interpreters with which such things may be read. It is clear from the description that these interpreters are the two stones that Joseph Smith later received, since the description corresponds so precisely: “And now he [Mosiah] translated them [the twenty-four gold plates] by the means of those two stones which were fastened into the two rims of a bow” (Mosiah 28:13).
Mosiah’s interpretation fulfills Ether’s prophecy that the two stones (interpreters) would be used to translate the twenty-four plates. But where did Mosiah get them? Limhi does not list them as part of the objects that his explorers brought back from the land of the Jaredites, and Mosiah already had them, or else Ammon would not have known about them. John Tvedtnes, examining the question of the two stones’ provenance, concludes: “The Lord could have retrieved the interpreters from their hiding place and given them to Mosiah. The Nephites of Zarahemla may have found the hiding place of the stones. They may have come into the possession of the Mulekites, who founded the city of Zarahemla, and then passed to Mosiah’s grandfather when he became king of that land.” I agree with Tvedtnes’s plausible provenance. Mosiah would have then received the stones among the ritual items featured during the merger of the Mulekites and Nephites.
Although this case is plausible, it is curious that Benjamin does not mention the stones when he invests Mosiah as the next king. Part of that ceremony is the formal transmission of “the records which were engraven on the plates of brass; and also the plates of Nephi; and also, the sword of Laban, and the ball or director, which led our fathers through the wilderness” (Mosiah 1:16). These sacred items have immense historical and religious importance: the brass plates, the plates of Nephi, the sword of Laban, and the Liahona. Why not the two stones? I hypothesize that this list consisted only of Nephite sacred objects. Despite the interpreters’ sacredness, they were not ritually significant in the validation of the political authority of the new king.
Redaction: Why did Mormon include this particular incident in his abridgment? Of course, we have no way of comparing its significance with items that Mormon omitted. Even if we had a list of omitted items, determining significance is highly subjective. A linguist might be most interested in a description of the plates. A metallurgist might be most interested in the apparent properties of both the “gold” (a notoriously soft metal) and the silver bow in which the stones were set. But why would this incident be important to Mormon?
It is too simple to say that the incident is important because of Ether’s text. Obviously, that content is important, but apparently not to Mormon. Mormon never abridged or edited the text and never left any indication of where he might have included that text in his work. He left it to Moroni to edit and add. At this point, Mormon includes an abbreviated conversation that says nothing about the subject matter of the plates, since Limhi and Ammon knew nothing about it. By the time he recorded this conversation, Mormon knew what the plates contained, but did not interject anything. (He later gives only the briefest of descriptions in Mosiah 28:17.) Consequently, Mormon included this exchange between Limhi and Ammon not because of the content of the plates but because it describes a seer. Mosiah’s spiritual prowess is what interests Mormon, not his linguistic abilities. (See also commentary accompanying vv. 16–17.)