God’s Testimony of the Book of Mormon
Doctrine and Covenants 17:6
6 And he [Joseph Smith] has translated the book [the Book of Mormon], even that part which I have commanded him, and as your Lord and your God liveth it is true.
Elder Bruce R. McConkie said:
“This [D&C 17:6] is God’s testimony of the Book of Mormon. In it Deity Himself has laid His godhood on the line. Either the book is true or God ceases to be God. There neither is nor can be any more formal or powerful language known to men or gods.”
(“The Doctrine of the Priesthood,” Ensign, May 1982, 33.)