Latter-day Saints believe that the Book of Mormon contain the “fullness of the gospel.” This is based on explicit statements in the revelations of Joseph Smith, such as:
Which [the Book of Mormon] contains a record of a fallen people, and the fullness of the gospel of Jesus Christ to the Gentiles and to the Jews also. (D&C 20:9)
Behold, this is wisdom in me; wherefore, marvel not, for the hour cometh that I will drink of the fruit of the vine with you on the earth, and with Moroni, whom I have sent unto you to reveal the Book of Mormon, containing the fullness of my everlasting gospel, to whom I have committed the keys of the record of the stick of Ephraim. (D&C 27:5)
He [Moroni] said there was a book deposited, written upon gold plates, gibing an account of the former inhabitants of this continent, and the source from whence they sprang. He also said that the fullness of the everlasting Gospel was contained in it, as delivered by the Saviour to the ancient inhabitants. (Joseph Smith History 1:34)
Opponents charge that this is false, as the Book of Mormon does not make explicit mention of certain Latter-day Saint beliefs and practices, such as pre-mortal existence; deification (eternal progression); the Aaronic Priesthood, and other doctrines and practices of the Church. Firstly, it should be noted that some of the beliefs critics claim to be absent in the Book of Mormon are present in the Book of Mormon, albeit implicitly. Theosis, for instance, is alluded to in 3 Nephi 28:10 and other passages. Often, critics will read their Protestant doctrine of formal sufficiency of Scripture (sola scriptura) into the Book of Mormon and other Latter-day Saint Scriptures, expecting/demanding to find an explicit reference to a certain doctrine. However, nothing in the Bible itself demands that there must be explicit scriptural witness for a doctrine to be true (our Presbyterian friends, for instance, will have to admit that there are no explicit references to infant baptism, and one must carefully compare and contrast the Old and New Covenants with one another, as well as the relationship of circumcision and baptism to covenantal membership with one another, alongside other topics, such as the issue of “household baptisms” in the Acts of the Apostles to arrive at such a doctrine).
On the issue of the doctrinal content of the Book of Mormon, I would recommend Mike Parker’s analysis of this issue, which is a response to a criticism by the late Walter R. Martin, author of The Maze of Mormonism and other poorly researched books (not just on “Mormonism”; speaking myself as an expert on Roman Catholicism, he made some howlers on Mariology and other topics in his debates with Jesuit scholar, Fr. Mitchell Pacwa).
Furthermore, the Book of Mormon itself is explicit that it contains only the lesser things (i.e., basic teachings) in 3 Nephi 26:1-12.
Many Latter-day Saints have also (correctly) pointed out that the term “gospel” simply means “good news,” and that the Book of Mormon defines the “gospel” in 3 Nephi 27:13-21 which records the very words of the resurrected Jesus Christ when He appeared in Mesoamerica after His resurrection:
Behold, I have given unto you my gospel, and this is the gospel which I have given unto you—that I came into the world to do the will of my Father, because my Father sent me. And my Father sent me that I might be lifted up upon the cross; and after that I had been lifted up upon the cross, that I might draw all men unto me, that as I have been lifted up by men even so should men be lifted up by the Father, to stand before me, to be judged of their works, whether they be good or whether they be evil—And for this cause have I been lifted up; therefore, according to the power of the Father I will draw all men unto me, that they may be judged according to their works. And it shall come to pass, that whoso repent and is baptised in my name shall be filled; and if he endureth to the end, behold, him will I hold guiltless before my Father at that day when I shall stand to judge the world. And he that endureth not unto the end, the same is he that is also hewn down and cast unto the fire, from whence they can no more return, because of the justice of the Father. And this is the word which he hath given unto the children of men. And for this cause he fulfilleth the words which he hath given, and he lieth not, but fulfilleth all his words. And no unclean thing can enter into his kingdom; therefore nothing entereth into this rest save it be those who have washed their garments in my blood, because of their faith, and the repentance of all their sins, and their faithfulness unto the end. Now this is the commandment: Repent, all ye ends of the earth, and come unto me and be baptised in my name, that ye may be sanctified by the reception of the Holy Ghost, that ye may stand spotless before me at the last day. Verily, verily, I say unto you, this is my gospel; and ye know the things that ye must do in my church; for the works which ye have seen me do that shall ye also do; for that which ye have seen me do even that shall ye do.
In the above pericope, the “gospel” is defined as being the good news about the life, divine mission, atoning sacrifice, triumphant resurrection, and further glorious final coming of Jesus Christ. As the Book of Mormon contains the most lucid explanations of the atonement of Jesus Christ (e.g. 2 Nephi 2; 9; Mosiah 15; Alma 34; 42), it qualifies as containing the fullness of the gospel.
In a number of revelations, the Lord commands the preaching of “the fullness of the gospel.” For instance, note these two texts from the Doctrine and Covenants, dating from 1836:
And cause that the remnant of Jacob, who have been cursed and smitten because of their transgression be converted from their wild and savage condition to the fullness of the everlasting gospel. (D&C 109:65)
And next spring let them depart to go over the great waters, and there promulgate my gospel, the fullness thereof, and bear record of my name. (D&C 118:4)
I find these two verses to be significant as they were revealed to Joseph Smith during a period of inscripturation, even according to opponents of the LDS Church. Obviously, during this time, various practices and doctrines were developing and were being revealed, and yet, Joseph Smith could command the preaching of the “fullness of the gospel” in 1836. One could argue that this is further evidence that the term does not mean “totality of doctrine and practices,” but a simpler concept, as outlined above.
Some opponents charge that D&C 42:12 teaches the Bible contains the fullness of the gospel and therefore the Book of Mormon is superfluous, even according to LDS teachings. The verse reads as follows:
And again, the elders, priests, teachers of this church shall teach the principles of my gospel, which are in the Bible and the Book of Mormon, in the which is the fullness of the gospel.
This is a rather superficial reading of the verse. The Bible is coupled with the Book of Mormon (note the use of the coordinating conjunction “and”), so the “fullness of the gospel” is either being said of the Book of Mormon alone of the Book of Mormon coupled with the Bible.
Finally, one anti-Mormon activist from Ireland, Desmond Ferguson (previously of Irish Church Missions) once argued in an article entitled “Witnessing to the Mormons” (Autumn 2005 issue of “The Banner of Truth” magazine by ICM) that the introduction of the Book of Mormon taught the Bible contained the fullness of the gospel, therefore, the Book of Mormon is not necessary (similar to the claims with D&C 42:12). However, the argument fails on a number of points. Firstly, the introduction to the Book of Mormon has never been considered as inspired or canonical, unlike the text of the Book of Mormon itself. The introductory page(s) of the various editions of the Book of Mormon have changed since 1830, alongside the (also uncanonical) introductions to the chapters one finds in the text.
Bruce McConkie, who was one of the main contributors to the introduction of the 1981 edition of the Book of Mormon, wrote:
[As for the] Joseph Smith Translation items, the chapter headings, Topical Guide, Bible Dictionary, footnotes, the Gazeteer, and the maps. None of these are perfect; they do not of themselves determine doctrine; there have been and undoubtedly now are mistakes in them. Cross-references, for instance, do not establish and never were intended to prove that parallel passages so much as pertain to the same subject. They are aids and helps only.
Source: Mark McConkie, ed. Doctrines of the Restoration: Sermons and Writings of Bruce R. McConkie (Salt Lake City, Utah: Bookcraft, 1989), 289–290.
Secondly, the introduction of the Book of Mormon was changed, as reflected in the 2013 printings of the LDS Scriptures. The introduction only predicates the “fullness of the gospel” on the Book of Mormon, without mention of the Bible:
The Book of Mormon is a volume of holy scripture comparable to the Bible. It is a record of God’s dealings with ancient inhabitants of the Americas and contains the fulness of the everlasting gospel.
Thirdly, using Ferguson’s “logic,” this is a disproof of the hypostatic union, as Jesus cannot be 100% God and 100% man, as one cannot have two “fullnesses,” as he claimed in his article.
Just a note to American readers: I am Irish, so there will be some differences in how I spell words (e.g. fullness vs. fulness) in this and other posts on this blog. Just fwiw.
