The Book of Nephi is a component of the religious text known as the Book of Mormon. It comprises the first two books within the larger Book of Mormon collection and outlines the spiritual and historical journey of a family who migrated from Jerusalem to the Americas around 600 BC. This narrative details their interactions with God, the establishment of a new civilization, and their encounters with Jesus Christ after his resurrection.
The absence of this scripture from the canonical Bible stems from its origins and acceptance within specific religious traditions. The Book of Mormon, including its initial books, was first published in 1830 by Joseph Smith. The Bible, on the other hand, is a collection of texts compiled and canonized over centuries by Jewish and Christian religious authorities. These authorities did not include the Book of Mormon or its constituent parts in their respective canons. This difference in origin and acceptance accounts for the distinction between the two religious texts.