Jacob, also known as Israel, is a central patriarchal figure in the Bible, and his descendants form the twelve tribes of Israel. The account of Jacob's descendants is primarily found in the Book of Genesis, with additional references throughout the Scriptures. Jacob had twelve sons and one daughter through his two wives, Leah and Rachel, and their maidservants, Bilhah and Zilpah. These sons became the progenitors of the tribes of Israel.

Leah's Children:

1. Reuben · Reuben was Jacob's firstborn son. Genesis 29:32 states, "And Leah conceived and bore a son, and she called his name Reuben, for she said, 'Because the LORD has seen my affliction; surely now my husband will love me.'" Reuben's descendants formed the tribe of Reuben.

2. Simeon · Leah's second son, Simeon, is mentioned in Genesis 29:33: "She conceived again and bore a son, and said, 'Because the LORD has heard that I am unloved, He has given me this son also.' So she named him Simeon."

3. Levi · Levi, the third son, is the ancestor of the Levites, the priestly tribe. Genesis 29:34 records, "Again she conceived and bore a son, and said, 'Now at last my husband will become attached to me, because I have borne him three sons.' Therefore he was named Levi."

4. Judah · Judah, the fourth son, is significant as the ancestor of King David and, ultimately, Jesus Christ. Genesis 29:35 states, "And she conceived again and bore a son, and said, 'This time I will praise the LORD.' Therefore she named him Judah. Then she stopped having children."

5. Issachar · Leah bore Issachar as her fifth son. Genesis 30:18 says, "Then Leah said, 'God has rewarded me for giving my maidservant to my husband.' So she named him Issachar."

6. Zebulun · Zebulun, Leah's sixth son, is mentioned in Genesis 30:20: "Then Leah said, 'God has presented me with a precious gift. This time my husband will treat me with honor, because I have borne him six sons.' So she named him Zebulun."

7. Dinah · Leah also bore a daughter named Dinah, as recorded in Genesis 30:21: "Afterward she bore a daughter and named her Dinah."

Rachel's Children:

1. Joseph · Rachel's firstborn, Joseph, is a key figure in the Genesis narrative. Genesis 30:24 states, "She named him Joseph, and said, 'May the LORD add to me another son.'" Joseph's descendants formed the tribes of Ephraim and Manasseh.

2. Benjamin · Rachel's second son, Benjamin, was born as she died in childbirth. Genesis 35:18 records, "As she was dying, she named her son Ben-Oni. But his father called him Benjamin."

Bilhah's Children (Rachel's Maidservant):

1. Dan · Dan was the first son of Bilhah. Genesis 30:6 states, "Then Rachel said, 'God has vindicated me; He has heard my voice and given me a son.' So she named him Dan."

2. Naphtali · Naphtali, Bilhah's second son, is mentioned in Genesis 30:8: "Then Rachel said, 'In my great struggles, I have wrestled with my sister and won.' So she named him Naphtali."

Zilpah's Children (Leah's Maidservant):

1. Gad · Gad was the first son of Zilpah. Genesis 30:11 records, "Then Leah said, 'How fortunate!' So she named him Gad."

2. Asher · Asher, Zilpah's second son, is mentioned in Genesis 30:13: "Then Leah said, 'How happy I am! For the women will call me happy.' So she named him Asher."

These twelve sons of Jacob became the patriarchs of the twelve tribes of Israel, each playing a unique role in the unfolding narrative of the Israelites. The tribes are frequently mentioned throughout the Old Testament, and their descendants are integral to the history and identity of the nation of Israel.