From the book, True to the Faith

The Book of Mormon came forth in this dispensation by the will of the Lord. It is a record of God’s dealings with the people who lived in the ancient Americas. Prophets of the Lord engraved the original records on gold plates. The Lord declared that the Book of Mormon contains “the fulness of the gospel of Jesus Christ” (D&C 20:9; see also D&C 42:12).

 On September 22, 1827, an angel named Moroni—the last Book of Mormon prophet—delivered these records to the Prophet Joseph Smith. By the gift and power of God, the Prophet Joseph translated the record into English. Since then, the Book of Mormon has been translated into many other languages. 

The primary purpose of the Book of Mormon is to convince all people “that Jesus is the Christ, the Eternal God, manifesting himself unto all nations” (title page of the Book of Mormon). It teaches that all people “must come unto him, or they cannot be saved” (1 Nephi 13:40). Joseph Smith said that the Book of Mormon is “the keystone of our religion, and a man [will] get nearer to God by abiding by its precepts, than by any other book” (introduction to the Book of Mormon). 

The Book of Mormon is another witness for the truths taught in the Bible. It also restores “plain and precious” truths that have been lost from the Bible through errors in translation or “taken away” in attempts to “pervert the right ways of the Lord” (see 1 Nephi 13:24–27, 38–41). The Bible and the Book of Mormon “shall grow together, unto the confounding of false doctrines and laying down of contentions, and establishing peace” (2 Nephi 3:12). 

Near the end of the Book of Mormon, the prophet Moroni teaches us how we can know the book is true: “When ye shall receive these things, I would exhort you that ye would ask God, the Eternal Father, in the name of Christ, if these things are not true; and if ye shall ask with a sincere heart, with real intent, having faith in Christ, he will manifest the truth of it unto you, by the power of the Holy Ghost” (Moroni 10:4; see also verses 3 and 5).