2 Nephi 6-10
Wherefore, as I said unto you, it must needs be expedient that Christ, (for in the last night the Angel spake unto me that this should be his name,) should come among the Jews, among they which are the more wicked part of the world; and they shall crucify him. — 2 Nephi 10:3
As a literary character, the Jesus Christ of the Book of Mormon operates something like Harry Lime, Orson Welles’ character in the brilliant 1949 noir film, The Third Man. Lime does not appear until the film is 2/3 over, and he only has fifteen minutes of screen time. But the entire film is thoroughly, absolutely, unquestionably, and obsessively about him; nothing in The Third Man makes sense without Harry Lime as a referent. So it is with Jesus Christ the Book of Mormon. 
The obsessive talking about Christ begins in 2 Nephi, Chapter 7 (or Chapter 10 if you insisting on using the modern edition). This is in Jacob’s brief interlude in his brother’s book, during which he reads two Messianic chapters of Isaiah (50 and 51) and discourses on the nature of the coming savior, referring to him first as “Messiah” and then, after a visit from an angel, as “Christ.” Later in 2 Nephi, Nephi adds that the Messiah/Christ’s given name would be Jesus. 
I have to admit that this used to bother me. A lot. It has always seemed so anachronistic to have Nephites and the occasional Lamanite talking about “Jesus Christ” 600 years before his birth–and expounding doctrines with an erie relevance to 19th century religious debates. This is so different from the Old Testament, which never mentions the name “Jesus” (except as the character Joshua, who has roughly the same Hebrew name), and the idea of a Messiah has to be carefully culled out of references that may or may not have been originally intended to apply to the future. The Book of Mormon always seemed to me to be trying too hard.
But here’s the thing that turned my thinking around: to read the Old Testament on its own terms  we must accept a lot more spooky stuff than we do when reading the Book of Mormon.
Let me explain: the traditional Christian interpretation of the Hebrew Bible holds that it speaks of Christ through the complicated discourse of typology. Its characters essentially live their lives as anticipatory symbols of New Testament events. To accept the Hebrew Bible as a text whose primary purpose is to testify of Christ (which is what “Old Testament” means), we must also accept that God manipulated several thousand years of human history in order to create some pretty vague narrative symbols: He told Abraham to sacrifice Isaac in order to point towards the crucifixion; He fed Jonah to the whale to prefigure the three days in the tomb; and He instituted an excruciatingly complicated system of animal sacrifice so modern Christians could read Leviticus and glimpse the truth about Christ’s substitutionary atonement.
By contrast, to accept the Book of Mormon on its own terms, one must only believe that God told prophets about some stuff that was going to happen in the future—which, when it comes to prophets, is kind of the point. In other words: to accept the Book of Mormon on its own terms, we must only accept its own terms.
And Jacob’s discourse about Christ in 2 Nephi is one of the most substantial discussions that we have in any of the Standard Works about what atonement means. And it is not just rehashing, either. As the following passage demonstrates, Joseph Smith was introducing some new and radical ideas about Christ’s atonement:
For as death hath passed upon all men, to fulfil the merciful plan of the Great Creator, there must needs be a power of resurrection, and the resurrection must needs come unto man by reason of the fall; and the fall came by reason of transgression; and because man became fallen, they were cut off from the presence of the Lord; wherefore it must needs be an infinite atonement; save it should be an infinite atonement, this corruption could not put on incorruption. Wherefore, the first judgment which came upon man, must needs have remained to an endless duration. And if so, this flesh must have laid down to rot and to crumble to its mother earth, to rise no more. (p. 79)
A religiously literate reader in 1830 would have seen at least three surprising assertions in this passage, which I list in ascending order of surprisingness:
- That Christ’s atonement was infinite in its scope and not limited to the elect, as most Calvinists believed. This was a major item of religious dispute at the time, and the BOM takes a definite stand.
- That the Resurrection effected by Christ’s atonement would be corporeal. This idea was not unknown at the time, but it was (and remains) unconventional. Joseph Smith, of course, would double down on this idea in a big way later in his career with the assertion that God himself is a resurrected and embodied being.
- That Adam and Eve’s Fall in the Garden of Eden was a good thing that had to happen for God to achieve His purposes—and that the Fall should be seen as a positive thing and not a negative one. Though there are precedents for this idea in the history of both Judaism and Christianity, it was not accepted by any denomination that I know of in 1830 and would have been seen as a radical departure by most practicing Christians.
In the historicity wars, of course, the detailed Christology of the Book of Mormon will remain a disputed phenomenon. One side will always see it as proof of a 19th century composition (“how else could supposedly ancient writers get Jesus’s first AND last names right?”), while the other will continue to offer it up as an example of the inspiration received by Nephi, Jacob, and Joseph Smith (“see, this just shows what really good prophet’s they were”).
But as I have said repeatedly in these #BOM2016 posts, I am not interested in debating historicity. I am interested in the text that we have in front of us, wherever it came from, and in the fact the text talks of Christ, rejoices in Christ, preaches of Christ, and prophecies of Christ—just like it says it does. Whatever one’s position on the larger issues of composition, it should mean something to say that the Atonement of Jesus Christ is the Book of Mormon’s central theme.
 All analogies break down at some point. This one breaks down at the point of imagining Orson Welles as Jesus Christ. Some levels of disbelief are not suspendable.
 Jacob’s shift from “Messiah” to “Christ” is a less spectacular revelation than one might suppose, as they mean the same thing (“anointed one”) in, respectively, Hebrew and Greek. Of course, “Messiah,” “Christ,” and “Jesus/Joshua” are actually English versions based on Hebrew and Greek words. And we have no reason to think that God actually taught Nephi and Jacob English, which means that the original words, under the book’s own terms, could have been very different, with the translations owing to Joseph Smith’s own linguistic and cultural assumptions.
 By “on its own terms” here, I mean on the terms that it can be considered the Old Testament. The presentation of this group of texts as part of the Christian canon embeds the assertion that they, like those of the New Testament, are primarily concerned with teaching readers about Christ. When the exact same texts are considered “the Tanakh,” or “the Hebrew Bible,” they no longer convey this expectation.