זוהר בראשית — דף קמד ע”א

The Zohar contrasts the speech of Jacob, who addressed his father with humility, with Esau’s “Let my father arise.” When Esau entered, Gehenna entered with him, and Isaac’s fear was greater than at the binding on the altar; Isaac said “he shall be blessed” because he saw the Divine Presence affirming the blessings. All affirmed them, even Esau’s own lot. The text then turns to Jacob’s struggle with the angel: angels who descend to this world clothe themselves in a body according to the custom of the place, and Esau’s dominion belongs to the night, that is, to exile, hence his weakness at dawn. “I will not let you go unless you bless me” means that he must acknowledge these blessings, and his name becomes Israel.