Genesis

⁴And Abraham circumcised his son Isaac when he was eight days old, as God had commanded him. ⁵And Abraham was an hundred years old, when his son Isaac was born unto him. ⁶And Sarah said, God hath made me to laugh; every one that heareth will laugh with me. ⁷And she said, Who would have said unto Abraham, that Sarah should give children suck? for I have borne him a son in his old age. ⁸And the child grew, and was weaned: and Abraham made a great feast on the day that Isaac was weaned. ⁹And Sarah saw the son of Hagar the Egyptian, which she had borne unto Abraham, mocking. ¹⁰Wherefore she said unto Abraham, Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, even with Isaac.