Jesus declares to the Nephites, "this people will I establish in this land, unto the fulfilling of the covenant which I made with your father Jacob" (3 Nephi 20:22). According to Richard D. Anthony, Jacob as the firstborn heir, needed to find a woman of the noble birthright. Also, he needed to flee for his life as the sibling rivalry "type" of Jesus and Lucifer, Cain and Abel, Ishmael and Isaac, was continued between him and Esau. Enmity between and among family members has always been prime cause for destruction of the eternal patriarchal or family covenant. Jacob's mother Rebecca directed him to her brother, Laban. Jacob's father Isaac blessed and confirmed her direction. Isaac also blessed Jacob at this time with the blessings of Abraham.
A pattern begins to emerge from the stories of each of the patriarchs--Abraham, Isaac and Jacob. Each was almost killed, or at least was threatened by a family member. Abraham was almost sacrificed on an altar, Isaac was threatened by Ishmael and Hagar. Jacob was threatened by Esau. They all left where they were and fled to another land. Here God blessed them. Although they had trials, they returned to the promised land better than they were before. The House of Israel also as a group went to another land, Egypt, had trials, but were delivered. Delivery was always by the firstborn and ultimate delivery will be by the firstborn son of God, even Jesus Christ. He will bring them back into the presence of His Father. The more we can see this type, rather than reading the Old Testament as a compilation of unrelated stories, the more we will be able to understand the prophecies of the Old Testament prophets, particularly Isaiah. This concept is the key to understanding Isaiah's message [and the Book of Mormon].
Jacob's marriage to Leah and Rachel set the stage for two blessings of the Lord to Abraham to be fulfilled. The Lord promised Abraham, that through his literal seed, the Messiah would be born, and the world would receive the blessings of the gospel, and salvation, and eternal life. This promise was fulfilled through Leah. She became the mother of Judah, and it is through the line of Judah that Mary, the mother of Jesus was born.
Through Rachel another promise to Abraham was fulfilled. This promise was that through Abraham's seed, or through his priesthood, all the nations of the earth would be blessed. It was through Rachel that Joseph, the firstborn, or birthright son was born. To him and to his descendants, Ephraim and Manasseh, the keys of the priesthood were given to bring not only the whole house of Israel to Christ, but also the gentiles.
All nations of the earth were blessed through Jesus Christ who is a blood descendant of Abraham, Isaac, and Jacob, and Sarah, Rebekah, and Leah, through Judah and Mary. Likewise all nations of the earth are blessed through Joseph and his posterity. It is through Joseph and his posterity that the keys of the priesthood are and were given to bring all to Christ. Both of these blessings were specifically promised to Abraham. The fulfillment of them was through Judah and his line, and Joseph and his line.
The Lord blessed Jacob in that Esau's enmity was abated, and they met and were reconciled one to another. Furthermore, God blessed Jacob, and changed his name to Israel and called him a prince (Genesis 32:28). The name Israel means one who prevails with God, or let God prevail. This name (the house of Israel) applied not only to Jacob, but to the literal descendants of Jacob, and to the true believers in Christ, regardless of their lineage or geographical location. [Richard D. Anthony, Isaiah and Joseph, pp. 35-37, unpublished manuscript] [See 2 Nephi 5:4-5]