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O Livro de Mórmon/Anacronismos/Bíblico/Citando Malaquias
Question: How can 1 Nephi 22:15 in the Book of Mormon quote Malachi 4:1 hundreds of years before Malachi was written?
The translation language may resemble Malachi, but the work is not attributed to Malachi
If Joseph was a fraud, why would he plagiarize the one text—the King James Bible—which his readers would be sure to know, and sure to react negatively if they noticed it? The Book of Mormon contains much original material—Joseph didn't "need" to use the KJV; he is obviously capable of producing original material.
The Book of Mormon claims to be a "translation." Therefore, the language used is that of Joseph Smith. Joseph could choose to render similar (or identical) material using King James Bible language if that adequately represented the text's intent.
The translation language may resemble Malachi, but the work is not attributed to Malachi. Only if we presume that the Book of Mormon is a fraud at the outset is this proof of anything. If we assume that it is a translation, then the use of Bible language tells us merely that Joseph used biblical language.
Joseph used entire chapters (e.g., 3 Nephi 12-14: based on biblical texts that he did not claim were quotations from original texts (even Malachi is treated this way by Jesus in 3 Nephi 24-25:. If these are not a problem, then a resemblance to biblical language elsewhere is not either, since that is simply how Joseph translated.