Isaac is Jacob’s father. Jacob’s mother is Rebekah, his twin brother is Esau, and his grandfather is Abraham. Genesis 25 gives the birth account in plain words: Isaac and Rebekah had twin sons, Esau first and Jacob second, when Isaac was sixty years old.
The birth account in Genesis 25
This is the passage that settles it. It names Isaac as the son of Abraham, names Rebekah as the wife of Isaac, and then records the birth of their twins.
This is the account of Abraham’s son Isaac. Abraham became the father of Isaac, and Isaac was forty years old when he married Rebekah, the daughter of Bethuel the Aramean from Paddan-aram and the sister of Laban the Aramean.
Later, Isaac prayed to the LORD on behalf of his wife, because she was barren. And the LORD heard his prayer, and his wife Rebekah conceived. But the children inside her struggled with each other, and she said, “Why is this happening to me?” So Rebekah went to inquire of the LORD, and He declared to her: “Two nations are in your womb, and two peoples from within you will be separated; one people will be stronger than the other, and the older will serve the younger.”
When her time came to give birth, there were indeed twins in her womb. The first one came out red, covered with hair like a fur coat; so they named him Esau. After this, his brother came out grasping Esau’s heel; so he was named Jacob. And Isaac was sixty years old when the twins were born.
Esau is Jacob’s twin brother, born moments earlier on the same day to the same parents. He is the same generation as Jacob, so he cannot be Jacob’s father.
Jacob names Isaac as his father, and so does God
Two later passages say it out loud rather than by implication. In the first, God speaks to Jacob at Bethel and places him in the line of Abraham and Isaac.
And there at the top the LORD was standing and saying, “I am the LORD, the God of your father Abraham and the God of Isaac. I will give you and your descendants the land on which you now lie.
In the second, Jacob prays on his way back to meet Esau and names his own father himself.
Then Jacob declared, “O God of my father Abraham, God of my father Isaac, the LORD who told me, ‘Go back to your country and to your kindred, and I will make you prosper,’
How often the Bible repeats this line
The three names run together as a set phrase. Counting the full Berean Standard Bible text, 27 separate verses name Abraham, then Isaac, then Jacob, in that order, inside a single verse. Eighteen of them are in the Old Testament and nine are in the New Testament. Esau appears in none of the 27.
One verse carries the whole line, from Abraham down to the twelve tribes, in a single sentence.
Then God gave Abraham the covenant of circumcision, and Abraham became the father of Isaac and circumcised him on the eighth day. And Isaac became the father of Jacob, and Jacob of the twelve patriarchs.
The family line from Abraham to the twelve tribes
The question is often really a family tree question, so here is the line with the verse for each step.
- Abraham and Sarah had one son together, Isaac (Genesis 21:2-3).
- Isaac married Rebekah and they had twin sons, Esau first and Jacob second (Genesis 25:20-26).
- God renamed Jacob Israel (Genesis 35:10).
- Jacob had twelve sons by four women: his wives Leah and Rachel, and their maidservants Bilhah and Zilpah (Genesis 35:23-26).
- Those twelve sons became the twelve tribes of Israel (Genesis 49:28).
The renaming comes first, and it is why Jacob and Israel are the same man in the text.
And God said to him, “Though your name is Jacob, you will no longer be called Jacob. Instead, your name will be Israel.” So God named him Israel.
The text lists the twelve by mother.
The sons of Leah were Reuben the firstborn of Jacob, Simeon, Levi, Judah, Issachar, and Zebulun. The sons of Rachel were Joseph and Benjamin. The sons of Rachel’s maidservant Bilhah were Dan and Naphtali. And the sons of Leah’s maidservant Zilpah were Gad and Asher. These are the sons of Jacob, who were born to him in Paddan-aram.
The other Jacob in the Bible
There is a second Jacob in scripture, and someone searching for the father of Jacob could mean him. Matthew’s genealogy of Jesus names a Jacob who is the father of Joseph, the husband of Mary. That Jacob’s father is Matthan.
The two men are in the same chapter. Matthew 1:2 names the patriarch Jacob near the top of the list, as the son of Isaac, and Matthew 1:15-16 names the other Jacob at the bottom of it, with Matthew’s three sets of fourteen generations in between (Matthew 1:17).
Eliud was the father of Eleazar, Eleazar the father of Matthan, Matthan the father of Jacob, and Jacob the father of Joseph, the husband of Mary, of whom was born Jesus, who is called Christ.
Jacob’s father in law is a different question
Jacob’s father in law is Laban. Laban was Rebekah’s brother, so he was Jacob’s uncle before he was anything else.
So Isaac sent Jacob to Paddan-aram, to Laban son of Bethuel the Aramean, the brother of Rebekah, who was the mother of Jacob and Esau.
Jacob went to Laban’s household and served him seven years for his younger daughter Rachel (Genesis 29:20), was given the older daughter Leah instead, then married Rachel as well and worked another seven years (Genesis 29:28 and Genesis 29:30). That is how his uncle became his father in law too.
Sources
Scripture on this page is the Berean Standard Bible, quoted word for word. The chapters can be read in full at BibleHub. Britannica gives the same parentage: Jacob is the son of Isaac, the grandson of Abraham, and the father of the ancestors of the twelve tribes of Israel.