The King James Version of the fourth chapter of Malachi begins with these two verses:
For, behold, the day cometh, that shall burn as an oven; and all the proud, yea, and all that do wickedly, shall be stubble: and the day that cometh shall burn them up, saith the Lord of hosts, that it shall leave them neither root nor branch. But unto you that fear my name shall the Sun of righteousness arise with healing in his wings; and ye shall go forth, and grow up as calves of the stall.
The fact that the word Sun is capitalized, even in modern editions of the KJV, suggests that some editor interpreted it as a reference to God or Christ. (Sunne is usually but not always capitalized throughout the original 1611 edition; modern editions do not capitalize sun except in this verse.) And indeed if you were to hear this passage read aloud it would be natural to misinterpret Sun as Son. Google Ngrams shows that, in literary use generally, people generally capitalize both nouns — Sun of Righteousness — implying that, although they may use the correct vowel in Sun, they are nevertheless interpreting the Sun as the Son and Righteousness as a name of the Father. And the solecism (or perhaps, in some cases, intentional wordplay) Son of righteousness, while much less frequent than the correct version, is far from rare.
But it is of course only in English that such confusion or wordplay comes naturally, since sun and son are not homophones in other languages. It might just pass muster as a pun in certain other Germanic languages (e.g. zon/zoon in Dutch), but certainly not in Malachi’s original Hebrew, where the word shemesh carries not the faintest echo of ben. In context, Malachi is clearly making no anachronistic allusion to the Son of God’s arising from the tomb, but is rather playing on the double nature of the sun’s heat. The Lord maketh his sun of righteousness to rise on the evil and the good — but the evil will experience it as a consuming fire; the good, as lifegiving warmth. (William Law makes this point eloquently, though without reference to Malachi, in his Spirit of Love.)
For us modern (post 17th-century) readers of the KJV, another factor encouraging the misinterpretation of Malachi is the use of the possessive determiner his, which seems more appropriately applied to a masculine son than to the inanimate sun. The word its did not make its literary début until several decades after the publication of the KJV — it appears once in modern editions (Leviticus 25:5) but not at all in the 1611 original — so his had to do double duty as the possessive determiner corresponding to both he and it. See for example Genesis 3:15 — “it shall bruise thy head, and thou shalt bruise his heel” — where it is clear that his is to it as thy is to thou. (Here, too, this archaic use of his may have influenced later readers to interpret the “seed” as a specific person, Christ, rather than in a more general sense.) However, Jacobean writers still felt a little uncomfortable with this neuter use of his, just as we feel vaguely uncomfortable writing “the car whose window is broken,” and they tended to avoid it. The KJV translators did this either by using such alternative locutions as thereof and of it, or — in the case of the sun — by poetically masculinizing a neuter noun. The KJV refers to the sun as it four times (when there is no accompanying possessive) and as he only twice (and only in sentences with his).
The Book of Mormon — purportedly written by the Nephites, American descendants of Hebrews who left the Old World circa 600 BC — quotes the third and fourth chapters of Malachi in their entirety, as chapters 24 and 25 of Third Nephi.
At first blush, this seems like a glaring anachronism, since Malachi prophesied circa 420 BC, long after Nephi and his family had left Jerusalem, and the Nephites should therefore have had no knowledge of his writings. The Book of Mormon has an explanation, though. The book of 3 Nephi deals with the visit of Jesus Christ to the Nephites following his resurrection, and in chapters 24 and 25, Christ — who did know the writings of Malachi — dictates them to the Nephites and “commanded them that they should write the words which the Father had given unto Malachi, which he should tell unto them” (3 Ne. 24:1). After the dictation — which for some reason includes only the second half of the Book of Malachi — is complete, Christ explains “These scriptures, which ye had not with you, the Father commanded that I should give unto you; for it was wisdom in him that they should be given unto future generations” (3 Ne. 26:2).
So quoting Malachi was not a mere ignorant blunder on Joseph Smith’s part. Whoever wrote the Book of Mormon clearly understood that the Nephites would not have had access to the Book of Malachi by any normal means and provided an explanation of how they could nevertheless know some of its contents.
There is still a blunder, though. In dictating Malachi 3-4 to the Nephites, when Christ comes to the passage discussed above, he says — you guessed it — “the Son of righteousness.” As discussed above, this is an error that would never have been made by Christ himself, nor by the Nephites who recorded his words, but only by an English speaker who knew the KJV but was not terribly literate. Joseph Smith fits the bill.
But then so do Joseph Smith’s scribes. After all, Smith didn’t actually write his English “translation” of the Book of Mormon but dictated it to an amanuensis — so it’s entirely possible that he translated the Nephites’ version of Christ’s dictation of Malachi correctly — “Sun of righteousness” — but that his scribe, misled by homophony, wrote down the wrong word, and that the error has been perpetuated in all subsequent editions of the book.
Unfortunately, Joseph Smith doesn’t get off the hook so easily, because 3 Nephi is not the only place where Malachi is quoted in the Book of Mormon. Material from Malachi also appears in 1 Nephi 22, and in 2 Nephi 25-26. These passages are far more problematic because they were supposedly written by Nephi, the son of Lehi, one of the original group that left Jerusalem in 600 BC and migrated to America. That is, they were written long before Christ appeared and dictated the words of Malachi — and Christ explicitly says in 3 Nephi that the Nephites had not had the Book of Malachi prior to his dictation. So how does the first Nephi come to be quoting from it?
Well, one possible explanation is that Nephi didn’t quote Malachi. After all, the entire Book of Mormon passed through the hands of Mormon and Moroni, who lived after Christ’s visit and thus had access to Malachi 3-4, so it is conceivable that the Malachi quotes represent later interpolations, not present in the original writings of Nephi. Sure enough, all the anachronistic Malachi quotations come from Malachi 4:1-2 — that is, from verses which were included in Christ’s partial dictation of the book — so Mormon and others would have had access to them. On the other hand, 1 and 2 Nephi come from the Small Plates of Nephi, and it is generally accepted that Mormon edited and abridged only the Large Plates, later appending the Small Plates complete and unmodified. Even if Mormon himself didn’t interpolate the Malachi quotes, though, someone else could have. Centuries passed between the revelation of Malachi to the Nephites and the final compilation of the Book of Mormon.
Another possibility is that the passages in question were written by Nephi, but that he was not quoting Malachi — that Malachi 4:1-2 is the work of some pre-exilic prophet whose work is now lost, and who was quoted by both Nephi and Malachi. In 1 Ne. 22, Nephi says “thus saith the prophet” (v. 15) and “this is according to the words of the prophet” (v. 23) when he quotes the Malachi material but does not mention Malachi by name. It’s just possible that he had some other prophet in mind, one whose writings survive only as unattributed quotations in the Book of Malachi.
Unfortunately, all these possible explanations are undermined by what we find in 2 Nephi 26:4-9, quoted below. The passages in bold show the clear influence of Malachi 4:1-2.
Wherefore, all those who are proud, and that do wickedly, the day that cometh shall burn them up, saith the Lord of Hosts, for they shall be as stubble. And they that kill the prophets, and the saints, the depths of the earth shall swallow them up, saith the Lord of Hosts; and mountains shall cover them, and whirlwinds shall carry them away, and buildings shall fall upon them and crush them to pieces and grind them to powder. And they shall be visited with thunderings, and lightnings, and earthquakes, and all manner of destructions, for the fire of the anger of the Lord shall be kindled against them, and they shall be as stubble, and the day that cometh shall consume them, saith the Lord of Hosts. O the pain, and the anguish of my soul for the loss of the slain of my people! For I, Nephi, have seen it, and it well nigh consumeth me before the presence of the Lord; but I must cry unto my God: Thy ways are just. But behold, the righteous that hearken unto the words of the prophets, and destroy them not, but look forward unto Christ with steadfastness for the signs which are given, notwithstanding all persecution—behold, they are they which shall not perish. But the Son of Righteousness shall appear unto them; and he shall heal them, and they shall have peace with him, until three generations shall have passed away, and many of the fourth generation shall have passed away in righteousness.
Yes, it’s the Son-with-an-o of Righteousness again, and this time the variant can’t easily be dismissed as an error on the part of Joseph Smith’s scribe. The context (i.e., coming right after two fairly direct quotations from Malachi 4:1) leaves little room for doubt that Malachi is being alluded to — but this time it is not a direct quote, and the rephrasing makes it clear that the Son (not the sun) is intended. This Son does not arise but appears, and “he shall heal them, and they shall have peace with him” is more unambiguously masculine than “with healing in his [its] wings.” Future editions of the Book of Mormon could easily correct 3 Nephi’s Son to Sun, but it wouldn’t be possible in 2 Nephi.
(In a somewhat parallel case, the original 1830 Book of Mormon frequently refers to the “straight and narrow” path — a very common solecism, reading straight for the KJV’s homophonous, but not synonymous, strait. More recent editions have quietly corrected all of these but one: 2 Ne. 9:41 — “Behold, the way for man is narrow, but it lieth in a straight course before him,” where the rephrasing makes it clear that straight means “straight,” not “strait.” Again, a mistake only an English speaker would make. This one is not as compelling as the Malachi case, though, since the context doesn’t make it so clear that it is intended as a biblical quotation.)