“I told the brethren that the Book of Mormon was the most correct of any book on earth, and the keystone of our religion, and a man would get nearer to God by abiding by its precepts, than by any other book.” (History of the Church,4:461.)
All truth should be measured against this book. It can draw us nearer to God by than any book or Men living today.
"If any man writes to you, or preaches to you, doctrines contrary to the Bible, the Book of Mormon, or the Book of Doctrine and Covenants, set him down as an imposter." (Joseph Smith, Times & Seasons, April 1, 1844)
We remain under condemnation until we believe what it's teaches, accept it, and abide by it's teachings even when it contradicts what men teach
D&c 84: 54 And your minds in times past have been darkened because of unbelief, and because you have treated lightly the things you have received
55 Which vanity and unbelief have brought the whole church under condemnation.
56 And this condemnation resteth upon the children of Zion, even all.
57 And they shall remain under this condemnation until they repent and remember the new covenant, even the Book of Mormon and the former commandments which I have given them, not only to say, but to do according to that which I have written.
How can we remember it when we don't teach or believe what it even says?