Per Martin Harris, Joseph confessed that he drank too much before translating the BOM and didn't know the contents of the BOM beforehand.

Feb 12, 1834
Meeting Minutes / Notes
Orson Hyde
Scribed Summary
2nd Hand

"Minute Book 1,” 28-29, 12 February 1834, The Joseph Smith Papers website, accessed August 11, 2021

Orson Hyde
Sidney Rigdon, Martin Harris, Joseph Smith, Jr., Orson Hyde, Alpheus C. Russell
General Public

The case of Bro. Martin Harris, against whom certain charges were preferred by bro. Sidney Rigdon, [was presented]. One was that he told Esqr. A. C. Russel that Joseph [Smith] drank too much liquor when he was translating the Book of Mormon and that he wrestled with many men and threw them &c. Another charge was that he exalted himself above bro. Joseph, in that he said bro. Joseph knew not the contents of the Book of Mormon until it was translated. Bro. Martin but that he himself knew all about it before it was translated. Bro. Martin said he did not tell Esqr Russell that bro. Joseph drank too much liquor while translating the Book of Mormon, but this thing took place before the Book of Mormon was translated. He confessed that his mind was darkened and that he had said many things, inadvertently calculating to wound the feelings of his brother and promised to do better. The council forgave him and gave him much good advice.

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