Quoting from Understanding the Book of Mormon: A Reader’s Guide by Grant Hardy

(Emphasis [in bold] added)

The Puzzle of the King James Version

Nephi’s exegetical methods are intriguing, and it might be interesting to compare them to nineteenth-century sermonizing, which often began from a scriptural passage and included key phrases;[11] to popular theology such as Ethan Smith’s View of the Hebrews, which also cited Isaiah to assert a connection between Native Americans and the ancient Israelites;[12] to New Testament readings of the Hebrew Bible, which uncovered Christian meanings in the ancient prophets; to Jewish Targums, which elaborated and interpreted as they translated the Bible scriptures into Aramaic;[13] or even to the pesharim of the Qumran community, which consisted of authoritative commentaries that demonstrated to the followers of the Teacher of Righteousness that the predictions of the prophets were being fulfilled in their own lives.[14] Indeed, more parallels could be cited—it is not unusual for religious traditions that revere particular texts to update the meanings of those writings so that they continue to be relevant in the lives of believers in successive eras—yet it is important to try to understand what Nephi himself thought he was doing within the context of the Book of Mormon narrative. Before we continue, though, there is another issue that needs to be addressed: the Book of Mormon’s long quotations from Isaiah inevitably raise questions about the translation/writing process. As we imagine Joseph looking into his seer stone and dictating to his scribes Nephi’s autobiography, it is reasonable to ask why there is so much Isaiah in this part of the Book of Mormon, and in particular why it appears in the language of the King James Bible.

For readers who see Smith as the author, the easiest explanation is that the eighteen chapters of Isaiah in First and Second Nephi are filler, employed when his creativity flagged or because he felt the need to pad the narrative so that its size was roughly equivalent to the 116 pages lost by Martin Harris.[15] Believers, on the other hand, often see the Isaiah portions as preserving a version of Isaiah older and more accurate than anything else available today.[16] Yet there are puzzling features of Nephi’s patterns of quotation that suggest that both of these explanations are too simplistic.

In the first place, unlike nearly everyone else in his religious environment, Joseph Smith is not simply quoting Isaiah from the Authorized Version; rather, he presents a modified form of the text. About half the quoted verses read differently from the King James Bible. However, it does not appear that these changes are always the result of intentional revision. Some are indeed inserted clauses or substituted phrases that clarify or expand Isaiah’s words, but there are also a great number of variants that make little or no difference to the meaning. These include substituted relative pronouns, transposed words, changes in number, alternative verb forms, omitted articles, and added conjunctions (such as for and yea).[17] For instance, both significant and trivia] changes can be seen in comparing Isaiah 13:15–18 with 2 Nephi 23:15–18 (following Royal Skousen’s reconstruction of the original text).[18] …

[refer to table in the original]

It is difficult to know what to make of all this. Some of the changes appear to be deliberate revisions (as in verse 15, where the two changes work in tandem, equating the “proud” and the “wicked,” making it less likely that proud for found is a copying error), others seem to he the sorts of changes that might occur when citing a text from memory, and there are sentences such as verse 17 that have been rendered less grammatical. It is also significant that a large percentage of the changes (Skousen estimates about one-third) are associated with the italicized words of the King James Version.[19]

It is possible that when Joseph Smith felt the need to quote Isaiah, he opened his Bible and read the chapters aloud, making whatever changes he deemed necessary. Yet this explanation does not account for the irregularities that we see—some of the alterations increase parallelism or make Isaiah easier to understand, while others fragment the text or make it more obscure (sometimes in ways that later editors of the Book of Mormon had to remedy, as when italicized forms of the be verb are dropped, making the grammar difficult to follow).[20] If Joseph thought it better to omit words in italics—easy enough if he had been working directly from the Bible—he did so inconsistently: in 2 Nephi 12–24 || Isaiah 2–14, italicized its are sometimes dropped and sometimes kept, and twenty-seven of thirty-seven instances of italicized is are retained.[21] In addition, many of the revisions work together to reflect a well-thought-out reinterpretation of Isaiah, while others are trivial and serve no obvious purpose. The situation is further complicated by the fact that Joseph’s wife, Emma, asserted that he never worked from a book or manuscript (which would have included the Bible), and there are no reports of Joseph having the kind of prodigious memory that would allow him to quote scripture by the chapter.[22]

It is striking that even though Joseph Smith sees the Authorized Version as authoritative, at the same time he appears comfortable modifying sacred writ. Equally remarkable is the fact that Nephi clearly expects that his writings will become scripture, with equal weight to Isaiah’s words. There is a demarcation between the quoted Isaiah passages and Nephi’s own prophecies, but this is not the sort of canon/commentary distinction common in the postbiblical world; Nephi is offering a new prophecy that is based on or responding to Isaiah. If some of what he says fits Joseph Smith’s nineteenth-century environment (such as the distinction made at 1 Ne. 22:1–3 between spiritual and temporal interpretations), it is nevertheless surprising how little attention Nephi gives to standard Christological readings.[23] He tells us that he is citing Isaiah because Isaiah “saw my Redeemer, even as I have seen him” (2 Ne. 11:2, cf. 1 Ne. 19:23), yet even though the chapters he reproduces include famous references such as Isaiah 7:14 (“a virgin shall conceive”) and 9:6 (“for unto us a child is born”), Nephi never mentions these verses in his comments. It is almost as if he does not recognize them as referring to Jesus.

Some Latter-day Saint scholars, despite Emma’s testimony, have accepted the hypothesis that Joseph Smith dictated the Isaiah chapters directly from an open Bible, with the proviso that his modifications were inspired by God and better reflected his ancient source.[24] Others believe that Joseph read from the seer stone a translation that had been previously prepared by God or his angels.[25] Yet in either case, the connection with any early Hebrew version of Isaiah is somewhat tenuous, and not merely because Nephi tells us that he only had access to an Egyptian transcription on the Brass Plates. Clearly the Book of Mormon Isaiah chapters, as we have them today, are based on the King James Bible, and as David Wright notes, “The alternative claim that the BM [Book of Mormon] is a translation but follows the KJV [King James Version] when the KJV is correct cannot be maintained since this cannot explain the preoccupation with italicized words, variants based on English polysemy, inconsistencies with Hebrew language and style and the persistence of KJV errors in the BM text.”[26] The Book of Mormon generally does not offer solutions to textual difficulties in the Hebrew, and readings from early manuscripts found since the time of Joseph Smith, such as the Dead Sea Scrolls, do not provide much support for the variants he introduced?[27]

For non-Mormon scholars, imagining the Brass Plates (ostensibly Nephi’s source) as a historic artifact from 600 BC is made even more difficult by the presence in the Book of Mormon of chapters from Second Isaiah (Isa. 40–55), which scholarly consensus for more than a century has attributed to the time of the Exile or even later (though, interestingly enough, the Book of Mormon never cites Third Isaiah [chs. 56–66]). Latter-day Saints sometimes brush such criticism aside, asserting that such interpretations are simply the work of academics who do not believe in prophecy, but this is clearly an inadequate (and inaccurate) response to a significant body of detailed historical and literary analysis.[28] William Hamblin has suggested that the problem might be alleviated if we regard Second Isaiah as a prophet contemporary with Nephi, but even this is not an entirely satisfactory solution.[29] Recent Isaiah scholarship has moved away from the strict differentiation of the work of First and Second Isaiah (though still holding to the idea of multiple authorship) in favor of seeing the book of Isaiah as the product of several centuries of intensive redaction and accretion. In other words, even Isaiah 2–14 would have looked very different in Nephi’s time than it did four hundred years later at the time of the Dead Sea Scrolls, when it was quite similar to what we have today.[30] A more promising avenue for the faithful, it seems, is to acknowledge that we probably know less about what constitutes an “inspired translation” than we do about ancient Israel. Once one accepts the possibility of divine intervention, the theology can accommodate the (always tentative) results of scholarship.[31] (emphasis added)

However one chooses to account for the parallel passages in the Book of Mormon and the Bible, it is clear that the former offers something of a midrash (to use an anachronistic term) on Isaiah. From the time of Ezra through the first centuries AD, Jewish rabbis developed a method of scriptural interpretation that sought to explain sacred writ though creative reinterpretation, clever wordplay, metaphor, and allegory. They wanted to uncover meanings that were not apparent in a surface reading. In so doing they placed emphasis on particular phrases and juxtapositions of events, and they tried to fill in the gaps of scripture imaginatively. These rabbis were not especially concerned with discovering the import of the words in their original ancient contexts (this is the task claimed by modern academic scholarship); rather, they were interested in updating the scriptures and reading their own circumstances and lives back into the text. The Oxford Dictionary of the lewish Religion defines midrash as “the discovery of meanings other than literal in the Bible; derived from the root darash (inquire), [it] denotes the literature that interprets scripture in order to extract its full implications and meaning. These interpretations often formed a response to the need of a particular age or environment.”[32]

This could easily describe Joseph Smith’s use of the King James Bible, but it also is true of Nephi’s reinterpretations of Isaiah. Skeptical readers may want to jump from the obvious dependence of the Book of Mormon on the Authorized Version right to the sensibilities of Joseph Smith—“There is no reason why Nephi should quote such a lengthy extract from Isaiah … so we need to look to Smith,” writes Dan Vogel—but this represents a failure of imagination.[33] Smith is not offering to the world his own commentary on Isaiah; everything in First and Second Nephi is depicted as coming through the mind of Nephi, and the appeal of the Book of Mormon is due in large part to the construction of Nephi as a unique and compelling voice.