He delivered him, as to the violent and certain despatch of his life which was intended. Or the act is here put for the purpose and endeavour of doing it, in which sense Balak is said to fight against Israel, Joshua 24:9, and Abraham to offer up Isaac, Hebrews 11:17. So here, he delivered him, i.e. used his utmost power to deliver him, that so he might recover his father's favour lost by his incestuous action.
Related Commentaries of Genesis 37:21
Genesis 37:21
21 And Reuben heard it, and he delivered him out of their hands; and said, Let us not kill him.