en_tn_condensed/rom/11/01.md

I say then

"I, Paul, say then"

did God reject his people?

Paul asks this question so that he can answer the questions of other Jews who are upset that God has included the Gentiles among his people, while the hearts of the Jewish people have been hardened.

May it never be.

"That is not possible!" or "Certainly not!" This expression strongly denies that this could happen. You may have a similar expression in your language that you could use here.

tribe of Benjamin

This refers to the tribe descended from Benjamin, one of the 12 tribes into which God divided the people of Israel.