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Joseph Smith Translation and the Book of Mormon
Algunos pasajes de la Biblia (partes de isaias por ejemplo)fueron incluidos en el texto del Libro de Mormon. sinembargo,los mismos pasajes fueron fueron revisados por la traduccion de la Biblia de Jose Smith.En algunos casos estos En algunos casos, estos pasajes no se representan de forma idéntica. Los críticos afirman que si la TJS fue una traducción exacta, que correspondería con el supuestamente más "puro" texto de Isaías que poseían los nefitas.
¿Por qué el Libro de Mormón coincida tan estrechamente con la version del rey Santiago RV?
Los críticos han adoptado la posición cínica de que José Smith simplemente se copia la versión del texto Boblico del Rey Santiago(RV) de las partes pertinentes, por ejemplo, Iasaias. Incluso algunos miembros de la Iglesia han supuesto que la estrecha relación entre los textos simplemente indica que José abrió una Biblia y copio los capítulos cuando llegó a la parte de las planchas de oro que él reconoce como de la Biblia.
¿Copio simplemente Jose copiar el texto del Rey Santiago RV?
Hay varios problemas con esta opinión.
1) Los testigos del proceso de traducción son unánimes en afirmar que José no tenia libros, manuscritos, notas o algo a que se pudiera referir al traducir. Emma recordó, en una entrevista posterior: Sé que el mormonismo es verdadero, y creo que la iglesia ha sido establecida con dirección divina. Tengo plena fe en ello. Por lo que [José] escribió con frecuencia, día tras día, a menudo sentada en la mesa cerca de él, sentado con el rostro enterrado en su sombrero, con la piedra dentro de el, y hora tras hora, dictando sin nada entre nosotros. P. ¿No había un libro o manuscrito que leia, o le dictaba a usted? A. No tenía ningun manuscrito o un libro para leer. P. ¿Lo podía haber tenido, y no lo sabia? A. Si hubiera algo de ese tipo no podría haber sido ocultado de mí . Martin Harris también señaló que José traducia con el rostro enterrado en su sombrero para usar la piedra del vidente/ Urim y Tumim. Esto haría que referenciar la Biblia o las notas fuera casi imposible: Joseph Smith ponia la piedra del vidente en un sombrero, y ponia su cara en el sombrero, tan cerca de la copa del sombrero para excluir la luz y brillara la luz espiritual en la oscuridad ... 
2) It is not clear that Joseph even owned a Bible during the Book of Mormon translation. He and Oliver Cowdery later purchased a Bible, which suggests (given Joseph's strained financial situation) that he did not already own one.
3) It is not clear that Joseph's Biblical knowledge was at all broad during the Book of Mormon translation. It seems unlikely that he would have recognized, say, Isaiah, had he encountered it on the plates. Recalled Emma Smith:
When my husband was translating the Book of Mormon, I wrote a part of it, as he dictated each sentence, word for word, and when he came to proper names he could not pronounce, or long words, he spelled them out, and while I was writing them, if I made a mistake in spelling, he would stop me and correct my spelling, although it was impossible for him to see how I was writing them down at the time. .?. . When he stopped for any purpose at any time he would, when he commenced again, begin where he left off without any hesitation, and one time while he was translating he stopped suddenly, pale as a sheet, and said, "Emma, did Jerusalem have walls around it?" When I answered, "Yes," he replied, "Oh! I was afraid I had been deceived." He had such a limited knowledge of history at the time that he did not even know that Jerusalem was surrounded by walls.
Emma also noted that Joseph Smith could neither write nor dictate a coherent and well-worded letter; let alone dictating a book like the Book of Mormon. And, though I was an active participant in the scenes that transpired, . . . it is marvelous to me, “a marvel and a wonder,” as much so as to any one else. And, if Joseph was merely inventing the Book of Mormon story, he picked some of the more obscure and difficult Bible passages to include.
4) If Joseph was forging the Book of Mormon, why include Biblical passages at all? Clearly, Joseph was able to rapidly produce a vast and complex text that made no reference to Biblical citations at all. If Joseph was trying to perpetrate a fraud, why did he include near-verbatim quotations from the one book (the Holy Bible KJV) with which his target audience was sure to be familiar?
Why then the KJV and Book of Mormon similarities?
Even academic translators sometimes copy a previous translation if it serves the purpose of their translation. For example, the discovery of the Dead Sea Scrolls (DSS) provided previously unknown texts for many Biblical writings. However, in some translations of the DSS, approximately 90% is simply copied from the KJV.
Surely we are not expected to believe that the DSS translators dropped back into King James idiom and just happened to come up with a nearly identical text! They, in fact, unabashedly copied the KJV, except where the DSS texts were substantially different from already known Hebrew manuscripts. 
Why was this done? Because, the purpose of the DSS translation is to highlight the differences between the newly discovered manuscripts and those to which scholars already had access. Thus, in areas where the DSS manuscripts agree with the Biblical texts that were already known, the KJV translation is used to indicate this.
This is not to argue that there may not be a better way to render the text than the KJV—but, it would be counterproductive for the DSS committee spent a lot of time improving on the KJV translation. A reader without access to the original manuscripts could then never be sure if a difference between the DSS translation and the KJV translation represented a true difference in the DSS, or simply the choice of the DSS translators to improve the KJV.
The situation with the Book of Mormon is likely analogous. For example, most of the text to which the Nephites had access would not have differed significantly from the Hebrew texts used in Bible translations. The differences in wording between the KJV and the Book of Mormon highlight the areas in which there were theologically significant differences between the Nephite versions and the Masoretic text, from which the Bible was translated. Other areas can be assumed to be essentially the same. If one wants an improved or clearer translation of a passage that is identical in the Book of Mormon and the KJV, one has only to go to the original manuscripts available to all scholars. Basing the text on the KJV focuses the reader on the important clarifications, as opposed to doing a new translation from scratch, and distracting the reader with many differences that might be due simply to translator preference.
Why is the JST different from the Book of Mormon?
Main article: Joseph Smith Translation as a restoration of the original Bible text
The Joseph Smith Translation of the Bible is not, as some members have presumed, simply a restoration of lost Biblical text or an improvement on the translation of known text. Rather, the JST also involves harmonization of doctrinal concepts, commentary and elaboration on the Biblical text, and explanations to clarify points of importance to the modern reader. (See main article on the nature of the JST for a more detailed discussion.)
Thus, the Book of Mormon is likely a relatively "tight" translation of the Nephite records, with the focus on the important differences between the Nephite textual tradition and the Masoretic text.
By contrast, the JST comes from a more prophetically mature and sophisticated Joseph Smith, and provides doctrinal expansion based upon additional revelation, experience, and understanding.
It is important to remember that Joseph did not consider one 'translation' of anything to be perfect or 'the final word.' Joseph had indicated that Moroni quoted Malachi to him using different wording than the KJV (See Joseph Smith History 1:36–39). However, when Joseph quoted the same passage years later in a discussion about vicarious baptism for the dead, he said:
I might have rendered a plainer translation to this, but it is sufficiently plain to suit my purpose as it stands. It is sufficient to know, in this case, that the earth will be smitten with a curse unless there is a welding clink of some kind or other between the fathers and the children, upon some subject or other-and behold what is that subject? It is the baptism. for the dead.(D&C 128:18.)
Thus, to Joseph, the adequacy of a translation depended upon the uses to which a given text will be employed. For one discussion, the KJV was adequate; for others, not. A key element of LDS theology is that living prophets are the primary instrument through which God continues to give knowledge and understanding to his children. Scriptures are neither inerrant, nor somehow "perfect," but are instead produced by fallible mortals. Despite this, because of current prophets and the revelation granted each individual, the writings of past prophets are sufficient to teach the principles essential for salvation. Additional revelation is sought and received as required.
An Example: The Lord's Prayer
There is a great example of this kind of difference in the Lord's prayer. Compare the following:
And lead us not into temptation, but deliver us from evil (Book of Mormon). And lead us not into temptation, but deliver us from evil (KJV Bible). And suffer us not to be led into temptation, but deliver us from evil (JST Bible).
The JST changes the statement to passive voice whereas the KJV Bible and the Book of Mormon are in active voice. According to E. W. Bullinger, this particular scripture contains a Hebraism, namely, "active verbs were used by the Hebrews to express not the doing of the thing, but the permission of the thing which the agent is said do." Consequently, Bullinger interprets the passage this way: "Lead us not (i.e., suffer us not to be led) into temptation." 
Adam Clarke agrees with Bullinger. He wrote this scripture means "'Bring not in,' or 'lead us not into.' (This is a mere Hebraism. God is said to do a thing which He only permits or suffers to be done)." 
In Barnes' Notes on the New Testament we read the same interpretation. "This phrase then must be used in the sense of permitting. Do not suffer us or permit us, to be tempted to sin. In this it is implied that God 'has such control over us and the tempter, as to save us from it if we call on him." 
When properly considered, this passage is an example of where the JST reading and the KJV/Book of Mormon are both correct. The KJV and Book of Mormon are literal interpretations while the JST is an interpretive translation that is also correct. Given Joseph's relative inexperience in prophetic interpretation in 1829, he would be far more likely to render a verse literally than engage in interpretation.
(And, as discussed above, the Book of Mormon translation may well have differed from the KJV only to indicate significant deviations in the base text, so the intent for each translation differed.) Conclusion
The purposes of the Book of Mormon and JST translations were not identical. The LDS do not believe in one fixed, inviolate, "perfect" rendering of a scripture or doctrinal concept. The Book of Mormon likely reflects differences between the Nephite textual tradition and the commonly known Biblical manuscripts. The JST is a harmonization, expansion, commentary, and clarification of doctrinally important points. Neither is intended as "the final word" on a given concept or passage—continuing revelation, adapted to the circumstances in which members of the Church find themselves, precludes such an intent.
Critics impose their own inerrantist assumptions on LDS scriptures, but such assumptions simply do not apply to LDS doctrine or scripture