The Book of Jacob is the third book in the Book of Mormon. Jacob, the brother of Nephi, was given the responsibility of writing down the history of his people. The purpose of this book, in the words of Jacob was to; “…persuade them [everyone] to come unto Christ…” (Jacob 1:7). The book is mainly the teachings between Jacob and his people, which include a lengthy Parable of the Olive Tree: which is an allegory of the scattering and gathering of Israel.
Around 545 BC, Jacob was given the task of continuing the history of the golden plates. At this time Nephi was soon to pass on, but the people revered him so much that they desired all the kings of the land to be like him and even named after him. The Jacobites, Josephites, and Zoramites all became the people of Nephi or the Nephites, while the Lemuelites and the Ishmaelites became the Lamanites.
The Nephites began to be lifted up in pride because they had been so blessed by God, and this led them to do wicked things. But Jacob and his brother Joseph tried as hard as they could to teach the people not to do wicked things. Jacob went to the temple to teach the Nephites. This temple was a copy of the one Solomon made in Jerusalem. Jacob said the people had begun to search for gold and silver. Some were better at locating the gold and silver and because of this, some would show that they were better or of a different social class, so they enhanced their apparel to show off that they were more ambitious and competent that their brothers.
Jacob then prophesied about events which would be fulfilled at the end of the Book of Mormon, around 385 AD, when the Nephites would be completely fallen away from God and wiped out to the last man by the Lamanites.
After a number of years a man named Sherem went around saying there would be no Christ, and for Jacob to preach the gospel of Christ instead of adherence to the Law of Moses was blasphemy. Jacob asserted that every prophesy ever made was really about Christ, and that it was revealed to him that if Christ does not make atonement, all humanity will be lost. Sherem demanded a sign to prove what Jacob said was true. Jacob explained that he would not tempt God.
God smote Sherem, making him fall unconscious for many days. When he eventually regained consciousness, he asked for the people to be assembled so he could make his last sermon. He confessed Christ, and said he had been deceived by the devil, and retracted everything he said about Jacob. He said he feared that he had committed the unpardonable sin, which is lying to God. Then he died.
When Jacob finished writing on the plates he bequeathed them to his son Enos.