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Source:David Whitmer:An Address to All Believers in Christ:8:1:I will say once more to all mankind, that I have never at any time denied that testimony or any part thereof
David Whitmer: "I have never at any time denied that testimony or any part thereof"
Parent page: Book of Mormon/Witnesses/Three witnesses
David Whitmer (1887): "I have never at any time denied that testimony or any part thereof"
Whitmer reasserts that he and the other two witnesses never denied their testimonies of the Book of Mormon, and quotes the last words of Oliver Cowdery:
It is recorded in the American Cyclopaedia and the Encyclopaedia Britannica, that I, David Whitmer, have denied my testimony as one of the three witnesses to the divinity of the Book of Mormon; and that the other two witnesses, Oliver Cowdery and Martin Harris, denied their testimony to that Book. I will say once more to all mankind, that I have never at any time denied that testimony or any part thereof. I also testify to the world, that neither Oliver Cowdery or Martin Harris ever at an time denied their testimony. They both died reaffirming the truth of the divine authenticity of the Book of Mormon. I was present at the death bed of Oliver Cowdery, and his last words were, “Brother David, be true to your testimony to the Book of Mormon." 
- David Whitmer, An Address to All Believers in Christ, page 8 (1887)