The Mormon scripture Doctrine and Covenants presents more serious problems. The original edition of Doctrine and Covenants was called the Book of Commandments and was published in 1833. This book contrained allegedly direct, word-for-word revelations from God to Joseph Smith. But in 1835 the Book of Commandments was reissued under the title Doctrine and Covenants and appeared with literally thousands of changes made from God's earlier revelations.

There are at least 65,000 changes between the Book of Commandments and Doctrine and Covenants. Joseph Smith had apparently changed his mind about what was and wasn't God's Word ¹³⁵

Nevertheless, the Mormon Church frequently claims that the Book of Mormon and Doctrine and Covenants have never been changed. Supposedly, there has been no tampering with "God's Word."¹³⁶ But the evidence is there for any Mormon to see. All interested readers may examine the issue for themselves by comparing modern versions with the first editions of the Book of Mormon and Doctrine and Covenants as found in Joseph Smith Begins His Work, Volumes 1 and 2 (notarized photostat copies)¹³⁷

A further point, briefly made here, but which should be of particular interest to many Mormons, is that Mormon teachings are not principally derived from the Book of Mormon. Mormon doctrine is derived primarily from another Mormon scripture, Doctrine and Covenants. [D&C]
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The dilemma that this poses for the Mormon church is a serious one because D&C emphasizes that the Book of Mormon contains basic, or fundamental, Mormon teachings. For example, according to D&C, the Book of Mormon contains "the truth and the Word of God" (D&:C, 19:26); "the fullness of the gospel of Jesus Christ" (that is, Mormon teachings, D&C, 20:9); and the "fullness of the everlasting gospel" (D&C, 135:3). Doctrine and Covenants also has Jesus claiming that the Book of Mormon has "the principles of my gospel" (D&C, 42:12) and "all things written concerning the foundation of my church, my gospel, and my rock" (D&C, 18:4, cf. 17:1-6; emphasis added [...]).

According to the Doctrine and Covenants then, the Book of Mormon must contain at the very least some of the central doctrines of the Mormon faith. But the Book of Mormon contains few major Mormon doctrines. It does not teach any of the following central Mormon principles, which form the foundation of the Mormon church and its "gospel": polytheism; God as the product of an eternal progression; eternal marriage; polygamy; human deification; the Trinity as three separate Gods; baptism for the dead; maintaining genealogical records; universalism; God has a physical body and was once a man; God organized, not created, the world; mother gods (heavenly mothers); temple marriage as a requirement for exaltation; the concept of eternal intelligences; three degrees of heavenly glory (telestial, terrestial, celestial); salvation after death in the spirit world; a New Testament era of Mormon organizational offices and functions such as the Melchizedek and Aaronic priesthoods; stake presidents and first presidency.

All this is why some Mormon writers have noted the theological irrelevance of the Book of Mormon to Mormonism.
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All this is why Mormon leaders tell potential converts to ignore criticism of the Book of Mormon and rely entirely upon subjective (completely personal) "confirmation."

Nevertheless, the church's appeal to subjectivity does nothing to convince a rational person why he or she should believe in the Book of Mormon. To believe without any evidence is troublesome enough; to believe in spite of the evidence is folly.

The Mormon scripture called the Doctrine and Covenants is a series of revelations which Joseph Smith and other LDS prophets claimed to receive directly from God. The first of these revelations were printed in The Book of Commandments in the year 1833. Since that time many of these revelations have been radically altered, with words and even whole sentences deleted. In other places later doctrinal innovations were written back into earlier revelations to hide the glaring contradictions that would otherwise result. In this way, events that were previously unheard of suddenly become part of the historical record as a revelation from God.

The Doctrine and Covenants contains 138 sections and two Official Declarations. The first 135 sections contain Joseph Smith’s revelations from 1823 to 1844, section 136 is a revelation by President Brigham Young in 1847, section 138 is one by President Joseph F. Smith in 1918. Declaration No. 1 is dated 1890 and is refered to as "The Manifesto" which declared an end to the practice of polygamy. Declaration No. 2 is dated 1978 and declared that "all worthy male members" could now hold the priesthood and participate in the temple ceremonies. This ended the LDS Church priesthood ban on Negroes.