Rigdon was named as likely author of the Book of Mormon on February 15, 1831:
“Rigdon was formerly a disciple of Campbell’s and who it is said was sent out to make proselytes, but is probable he thought he should find it more advantageous to operate on his own capital, and therefore wrote, as it is believed the Book of Mormon, and commenced his pilgrimage in the town of Kirtland, which was represented as one of the extreme points of the Holy Land.”
Anon. (1831). Mormonism – or Grand Pugilistic Debate. Cleveland Advertiser, February 15, 1831.
Possible reasons Rigdon was suspected early on of being the author:
1. His apparent foreknowledge of the book prior to March, 1830.
2. His theology appeared throughout the book.
3. He almost immediately advanced to a position co-equal to Smith after his baptism.
Evidence of his apparent foreknowledge of the book:
Said Darwin Atwater, a Patriarch in the Disciples Church at Mantua:
“That he [Rigdon] knew before of the coming of The Book of Mormon is to me certain, from what he said the first of his visits to my father’s some years before [at about the close of January 1827]”. “He gave a wonderful description of the mounds and other antiquities found in some parts of America, and said they must have been made by the aborigines. He said there was a book to be published containing an account of those things. He spoke of these in his eloquent, enthusiastic style as being a thing most extraordinary.”
Dr. Storm Rosa, a well-known “botanic physician” of Ohio, said in, an 1841 letter to Rev. John Hall of Ashtabula:
“In the early part of the year 1830 I was in company with Sidney Rigdon, and rode with him on horseback for a few miles…. He remarked to me that it was time for a new religion to spring up; that mankind were all right and ready for it.”
In a Jan 22, 1841 letter written to Walter Scott, Adamson Bentley said:
“I know that Sidney Rigdon told me that there was a book coming out, the manuscript of which had been found engraved on gold plates, as much as two years before the Mormon Book made its appearance, or had been heard of by me.”
Thomas Clapp, a deacon in the church where Rigdon preached, confirmed Bentley’s statement:
“Elder Adamson Bentley told me that as he was one day riding with Sidney Rigdon and conversing upon the Bible, Mr. Rigdon told him that another book of equal authority with the bible, as well authenticated and as ancient, which would give an account of the history of the Indian tribes on this continent, with many other things of great importance to the world, would soon be published. This was before Mormonism was ever heard of in Ohio, and when it appeared, the avidity with which Rigdon received it convinced him that if Rigdon was not the author of it he was at least acquainted with the whole matter some time before it was published to the world.”
The Reverend Samuel F. Whitney said:
“I heard Sidney Rigdon preach in Squire Sawyers’ orchard in 1827 or ’28. He said how desirable it would be to know who built the forts and mounds about the country. Soon it would all be revealed. He undoubtedly referred to the “Book of Mormon” which was published in 1830.”
John Rudolph stated:
“For two years before The Book of Mormon appeared Rigdon’s sermons were full of declarations and prophecies that the age of miracles would be restored, and more complete revelations, than those in the Bible, would be given. When The Book of Mormon appeared, all who heard him were satisfied that he referred to it.” (Cowdery et al., 2005, p. 313).
Reuben P. Harmon said:
“My parents came to Ohio from Vermont in 1815. I resided in Kirtland when the Mormons first arrived. I was personally acquainted with Rigdon….I have heard [him] several times say in his sermons that before long the Indian mounds and forts about there would all be explained. He caused a row of log houses to be built on Isaac Morley’s farm, and established a Communistic Society before Mormonism was heard of. I heard Rigdon preach his first sermon at Kirtland Flats, and after he embraced Mormonism. He said that he had been preaching wrong doctrine and asked their forgiveness…” (Cowdrey et al., 2005, p. 313).
Smith-as-Sole-Author advocates explain the above statements as information Rigdon acquired from local newspaper accounts prior to publication of The Book of Mormon. Newspapers published at Rochester, NY, on August 31 and Sept 5, 1829, indicated that Smith’s activities were known in Palmyra and vicinity as early as the fall of 1827. (Van Wagoner,1994, pages 55-56). A November 16, 1830 article in the Painesville Telegraph entitled “The Golden Bible” reported:
“Some two or three years since, an account was given in the papers, of a book purporting to contain new revelations from Heaven, having been dug out of the ground in Manchester, Ontario County, NY.”