Nephi teaches that many plain and precious truths that were once had among the Jews have not made it into the Bible handed down to us via the Gentiles. We tend to talk as though these are truths revealed by Christ, but not passed on as his church fell into apostasy. But could many of these be truths lost before the time of Christ, or revealed before Christ but lost shortly after he left the Earth?
Nephi’s vision refers repeatedly to “the book of the Lamb of God, which had proceeded forth from the mouth of the Jew” and says that “when it proceeded forth from the mouth of a Jew it contained a fulness of the gospel of the Lord” (1 Nephi 13:24). The vision prominently features the coming of the Lamb of God and the ministry of his disciples, and then talks about the great and abominable church that “take[s] away from the gospel of the Lamb many parts which are plain and most precious” (1 Nephi 13:26). The description of the vision naturally leads to the impression that the loss of truths happened after the coming of Christ, and that the truths lost were truths he revealed (it is after all the book of the Lamb of God).
Yet, the angel also says, “The book that thou beholdest is a record of the Jews, which contains the covenants of the Lord, which he hath made unto the house of Israel; and it also containeth many of the prohecies of the holy prophets . . .” (1 Nephi 13:23). This would be material revealed to the Jews long before Christ. Could it be that many of the truths that were lost are truths that were had among the Jews before the time of Christ? Like the patriarchal practice of sacrifice, which did not require a temple, and which Lehi practiced in the desert, but which appears to have been frowned upon by later Jewish orthodoxy? Or, well, the message of Christ preached by Abraham and Moses, to which Christ referred in his condemnations of the Jewish establishment? And then there is the stuff about God’s wife.
Christ clearly regards the Jews of his time as not merely lacking the higher law, but as having apostasized from the truths Moses gave them. Could it be that the Jewish apostasy is responsible for the loss of truth from the (precursors to the) Bible to a similar degree as the Christian apostasy?