Jacob or Ya'akov, (יַעֲקֹב "Holder of the heel"), later known as Israel (יִשְׂרָאֵל "Prince of God") is the third Biblical patriarch. His father was Isaac and his grandfather was Abraham. His story is told in the Book of Genesis.
Jacob was born 20 years after Isaac and Rebekah were married, at which time his father was 60 (Gen. 25:26), and Abraham, 160 years old. He and his twin brother, Esau, were markedly different in appearance and behavior. Esau was a ruddy hunter, while Jacob was a gentle man who "dwelled in tents," interpreted by most biblical scholars as a mark of his studiousness in the "tents" of Torah.
During Rebekah's pregnancy, "the children struggled together within her" (Genesis 25:22).