Genesis 25:5-6

25:5 Everything he owned Abraham left to his son Isaac. 25:6 But while he was still alive, Abraham gave gifts to the sons of his concubines and sent them off to the east, away from his son Isaac.

Genesis 25:32

25:32 “Look,” said Esau, “I’m about to die! What use is the birthright to me?”

Genesis 25:34

25:34 Then Jacob gave Esau some bread and lentil stew; Esau ate and drank, then got up and went out. So Esau despised his birthright.