In to the Book of Mormon, the Liahona is a brass ball with two spindles, one of which directs where Lehi and his companions should travel after they leave Jerusalem at the beginning of the narrative. Some early participants in the Latter Day Saint movement, believing contrary to mainstream findings that the Book of Mormon described genuinely historical events, claimed to have seen the Liahona. The Church of Jesus Christ of Latter-day Saints and its members have used the Liahona as a namesake, such as in the name of the magazine the Liahona and in the idea of "Liahona Mormons".

According to the Book of Mormon, Lehi was a prophet who lived in Jerusalem during the reign of King Zedekiah. In First Nephi, Lehi is rejected for preaching repentance and he leads his family, including Sariah, Laman, Lemuel, Sam, and Nephi, into the wilderness. He sends his sons back to recover the plates of brass and once more for the family of Ishmael. As they travel, Lehi has a vision of the tree of life in which most of his family, excepting Laman and Lemuel, accepts God. He also prophesies Christ's coming 600 years in the future.