Yitzchak (Isaac) was forty years old when he married Rivka (Rebecca). After twenty years Rivka becomes pregnant with twins. She receives a prophecy that the older son will be subservient to the younger. The eldest twin is born covered in hair, and he is called Esav (Esau) meaning fully made. The second son is clutching the heel of his brother and therefore he is called Ya’akov (Jacob) derived from Ekev, heel. Esav becomes a hunter, while Ya’akov remains a quiet tent dweller. Yitzchak loves Esav, whereas Rivka favours Ya’akov. Esav gives up his rights as firstborn to Ya’akov in exchange for lentil stew, thus showing contempt for his birthright.
There is a famine in Israel and Yitzchak and Rivka go to Gerar. They claim that they are brother and sister, but Avimelech the king sees them involved in intimacy and realises that they are husband and wife. He decrees that any of his subjects who harm them will be killed. Yitzhak is very successful in his agricultural endeavours, and is therefore forced to leave Gerar because of the jealousy of the residents. He redigs the wells that Avraham had dug, but which had subsequently been covered over by the Plishtim. When he returns to Beer Sheva, G-d appears to him and confers upon him the blessing that He had previously given to Avraham. Avimelech approaches Yitzchak and they sign a non-belligerence pact.
At the age of forty, Esav marries Yehudis and Bosmas, which causes bitterness to Yitzchak and Rivka. As Yitzchak approaches old age, he tells Esav to bring him a meal, in order that he may bless his son before his death. Rivka overhears and, based on the prophecy she had before her sons were born, instructs Ya’akov to impersonate his brother so that he should receive this blessing in Esav’s stead. Yitzchak perceives that the hands are the hands of Esav, but the voice is the voice of Ya’akov. He blesses him with material prosperity and power. As Ya’akov leaves, Esav enters with the meal he has prepared. Yitzchak realises what has happened and confirms his blessings to Ya’akov. He tells Esav that he has no further blessing that he can give, but informs him that if Ya’akov rebels against G-d, Esav will be able to throw off his brother’s yoke and gain the upper hand. Esav hates Ya’akov and plans to kill him after their father’s death. Rivka suggests to Yitzchak that they send Ya’akov away to Lavan, her brother, to find a wife. Before he departs, Yitzchak bestows upon Ya’akov the blessing that G-d had given both to him and to Avraham. Ya’akov leaves for Padan Aram. Esav marries a third wife, Machalas bas Yishmael, granddaughter of Avraham