Genesis 25:21-23

ISV(i) 21 Later, Isaac prayed to the LORD on behalf of his wife, since she was unable to conceive children, and the LORD responded to him—his wife Rebekah became pregnant.
22 But when the infants kept on wrestling each other inside her womb, she asked herself, “Why is this happening?” So she asked the LORD for an explanation.
23 “Two nations are in your womb,” the LORD responded, “and two separate people will emerge. One people will be the stronger, and the older one will serve the younger.”