Mosiah 8:5 the plates which contained the record of his people
The large plates of Nephi were kept by Mosiah in Zarahemla and are different than these plates. Limhi's plates contain the record of his people from the days of king Zeniff to his day. This is the record from which Mormon will take his abridgment, comprising Mosiah 9-22. We must remember that there are many sets of plates other than the large and small plates of Nephi. In this chapter, we learn of the plates of Limhi's people and the 24 gold plates of the Jaredites.
Mosiah 8:7-8 forty and three of my people...discovered a land which was covered with bones
The Book of Mormon does not specifically give the time of the destruction of the Jaredites. By the time of Limhi, they had been dead long enough that their swords had decayed, the hilts thereof have perished, and the blades thereof were cankered with rust (v. 11). On the other hand, they had breastplates which were still in good condition (v. 11). Coriantumr had stayed with the Mulekites in Zarahemla for 9 months signifying that the Jaredites were still alive after the Nephites and Mulekites arrived (Omni 1:21). Nevertheless, the Jaredites were wise enough to preserve their record on gold plates and provide a Urim and Thummim for the interpretation of their record.
The geography of the Book of Mormon is not that important, but it is helpful to have a mental map for the next several chapters. This passage gives us a clue to the relationship between the city of Lehi-Nephi, Zarahemla, and the land of the Jaredites. This small band of forty-three people would have headed north to find Zarahemla. That they found the land of the Jaredites is not surprising because the Jaredites were known to inhabit the lands of the north (Alma 22:29-30). Alma 22 demonstrates that the land of the Jaredites was farther north than was Zarahemla.
Mosiah 8:8 a people who were as numerous as the hosts of Israel
This is a pretty good clue to the size of the Jaredite civilization because we know the number of the hosts of Israel. While in Sinai, the Lord commanded Moses to number the hosts of Israel. The result of the census was that there were 603,550 men over age 19 (Num 1:45-47). This number excluded all women, children, and the tribe of Levi which was later counted to have 22,000 men and boys (Num 3:39). Therefore, the total number of the camp must have been well over 1 million people, and the Jaredites also must have numbered in the millions. Near the end of the Jaredite civilization, Coriantumr mourns that two millions of his people had been slain by the sword (Ether 15:2).
Mosiah 8:9 they have brought twenty-four plates which are filled with engravings
"The twenty-four plates were called The Book of Ether after its author. (Ether 1:2) Their discovery was not an accident. For, when Ether had finished his record, 'He hid them in a manner that the people of Limhi did find them.' (Ether 15:33)" (Reynolds and Sjodahl, Commentary on the Book of Mormon, vol. 2, p. 283)
Mosiah 8:13 the things are called interpreters
The interpreters are the Urim and Thummim that the Lord had given to the brother of Jared (Ether 3:23; 4:5). The brother of Jared wrote his vision of the inhabitants of the earth in the Jaredite form of the Adamic language. The Lord knew that no subsequent people would be able to interpret this language without divine help. The Urim and Thummim were designed just for a seer like Mosiah to use to translate the record. Apparently, Mosiah had received the interpreters which were had by the kings. His grandfather (also named Mosiah) had used them to interpret the large stone of the Jaredites (Omni 1:20). The term used when describing translation with the Urim and Thummim is 'by the gift and power of God.' This is the way we describe the translation of the Book of Mormon, by the gift and power of God (Moroni's Title Page).
This same Urim and Thummim spoken of in Mosiah 8:13 is the Urim and Thummim that was buried with the gold plates. It was the tool which Joseph Smith used to translate the Book of Mormon-especially early on. He described them as follows, there were two stones in silver bows-and these stones, fastened to a breastplate, constituted what is called the Urim and Thummim-deposited with the plates; and the possession and use of these stones were what constituted "seers" in ancient or former times; and that God had prepared them for the purpose of translating the book. (JS-H 1:35). This Urim and Thummim was taken with the plates by Moroni after Joseph was done translating.
There was at least one more Urim and Thummim because Abraham had one (Abr 3:1) and Moses had one that was placed in the breastplate of judgment (Ex 28:30).
Bruce R. McConkie
"The Hebrew words urim and thummim , both plural, mean lights and perfections. Presumably one of the stones is called Urim and the other Thummim. Ordinarily they are carried in a breastplate over the heart. (Ex. 28:30; Lev. 8:8)...President Joseph Fielding Smith, with reference to the seer stone and the Urim and Thummim, has written: ' We have been taught since the days of the Prophet that the Urim and Thummim were returned with the plates to the angel. We have no record of the Prophet having the Urim and Thummim after the organization of the Church.'" (Mormon Doctrine, p. 818)
Mosiah 8:15 a seer is greater than a prophet
The best explanation of a seer is contained in Mosiah 8. A seer is a translator, the one with the right to use the Urim and Thummim to inquire about the mind and will of the Lord. Verse 17 seems to indicate that a seer has a greater capacity to reveal secret things and the hidden things of God. The Old Testament lists some prophets who were also seers but many of the names are less familiar, Samuel, Zadok, Gad, Heman, Iddo, Hanani, Asaph, Jeduthun, and Amos (see TG-Seer).
The President of the Church is the active seer in our dispensation. The D&C teaches, the duty of the President of the office of the High Priesthood is to preside over the whole church, and to be like unto Moses-Behold, here is wisdom; yea, to be a seer, a revelator, a translator, ad a prophet, having all the gifts of God which he bestows upon the head of the church (DC 107:92). This same gift of seership is bestowed upon all the men who are ordained as apostles. Every General Conference, the Apostles and First Presidency are sustained as prophets, seers, and revelators.
"'A seer, ' wrote Elder John A. Widtsoe, 'is one who sees with spiritual eyes. He perceives the meaning of that which seems obscure to others; therefore he is an interpreter and clarifier of eternal truth. He foresees the future from the past and the present. This he does by the power of the Lord operating through him directly, or indirectly with the aid of divine instruments such as the Urim and Thummim. In short, he is one who sees, who walks in the Lord's light with open eyes.' (Evidences and Reconciliations, p. 258.)" (McConkie and Millet, Doctrinal Commentary on the Book of Mormon, vol. 2, p. 192)
The best example of a seer in our generation is the work and ministry of Joseph Smith, referred to by Joseph of Egypt as a choice seer (2 Ne 3:6).
"The ancient prophet Enoch was privileged to behold things 'which were not visible to the natural eye; and from thenceforth came the saying abroad in the land: A seer hath the Lord raised up unto his people' (Moses 6:36). As the past is but a pattern for the future, so too in our day has God raised up a seer, a 'choice seer' in the land, one who indeed was allowed entrance within the veil and was enabled to see things 'afar off' (D&C 101:54). Joseph Smith was called of God in this final dispensation to stand as a prophet, a seer, a revelator of sacred matters, a covenant spokesman among modern Israel." (Millett and McConkie, Joseph Smith, the Choice Seer, Preface)
Mosiah 8:19 Doubtless a great mystery is contained within these plates
The great mystery contained on the 24 plates includes the Book of Ether. Moroni said, I take mine account from the twenty and four plates which were found by the people of Limhi, which is called the Book of Ether (Ether 1:2). But Moroni abridged the record and did not include all of the prophecies of the brother of Jared. They were withheld because of their greatness, for the Lord showed unto the brother of Jared all the inhabitants of the earth which had been, and also all that would be (Ether 3:25). This great revelation is to come forth when the people are ready, in that day that they shall exercise faith in me, saith the Lord even as the brother of Jared did, that they may become sanctified in me, then will I manifest unto them the things which the brother of Jared saw, even to the unfolding unto them all my revelations (Ether 4:7).