Therefore she said to Abraham, "Cast out this bondwoman and her son; for the son of this bondwoman shall not be heir with my son, namely with Isaac."
Genesis 21:10
Surrounding context
21:9 And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, scoffing.
21:10 Therefore she said to Abraham, "Cast out this bondwoman and her son; for the son of this bondwoman shall not be heir with my son, namely with Isaac."
21:11 And the matter was very displeasing in Abraham's sight because of his son.