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O Livro de Mórmon/Teorias de Autoria/Sidney Rigdon
Sidney Rigdon: "in all of my intimacy with Joseph Smith he never told me but one story"
Sidney Rigdon to his son John, just prior to Sidney's death, asserted that the Book of Mormon was true:
My father, after I had finished saying what I have repeated above, looked at me a moment, raised his hand above his head and slowly said, with tears glistening in his eyes: "My son, I can swear before high heaven that what I have told you about the origin of [the Book of Mormon] is true. Your mother and sister, Mrs. Athalia Robinson, were present when that book was handed to me in Mentor, Ohio, and all I ever knew about the origin of [the Book of Mormon] was what Parley P. Pratt, Oliver Cowdery, Joseph Smith and the witnesses who claimed they saw the plates have told me, and in all of my intimacy with Joseph Smith he never told me but one story. 
Pergunta: Por que alguns críticos acreditam que Sidney Rigdon foi o autor do Livro de Mórmon?
Initial reaction to the Book of Mormon attributed the authorship to Joseph Smith himself, and reviewers were quick to criticize the book's problems of style, and simply declared it an obvious, amateurish forgery.
It seems to have soon become clear, however, that Joseph truly was incapable of writing such a book. As a result, Sidney Rigdon, an experienced minister, was soon blamed for the book, with Joseph as a willing fellow-con:
[1 September 1831] ...the money diggers of Ontario county, by the suggestions of the Ex-Preacher from Ohio [i.e., Rigdon], thought of turning their digging concern into a religious plot, and thereby have a better chance of working upon the credulity and ignorance of their associates and the neighborhood. Money and a good living might be got in this way....
There is no doubt but the ex-parson from Ohio is the author of the book which was recently printed and published in Palmyra, and passes for the new Bible. It is full of strange narratives—in the style of the scriptures, and bearing on its face the marks of some ingenuity, and familiar acquaintance with the Bible. It is probable that Joe Smith is well acquainted with the trick, but Harris the farmer and the recent coverts, are true believers....
They were called translations, but in fact and in truth they are believed to be the work of the Ex-Preacher from Ohio, who stood in the back ground and put forward Joe to father the new bible and the new faith.
- Rex C. Reeve, Jr. "What is 'Manuscript Found'?" in Manuscript Found: The Complete Original "Spaulding" Manuscript, edited by Kent B. Jackson, Vol. 11 in the Specialized Monographs Series (Religious Studies Center, Brigham Young University, 1996), footnote 47.
- “Mormon Religion—Clerical Ambition—Western New York—The Mormonites Gone to Ohio,” Morning Courier and New-York Enquirer (New York City, New York) 7, no. 1331 (1 September 1831). off-site