The thing was very grievous in Abraham’s sight. — Heb., the word (or matter) was evil exceedingly in Abraham’s eyes. It was not merely painful to him because of his natural affection for Ishmael (Genesis 17:18), but he also thought the proposal unjust.
Related Commentaries of Genesis 21:11
Genesis 21:11
11 And the thing was very grievous in Abraham's sight because of his son.