en_tn/rom/09/08.md

the children of the flesh

This refers to people who are the physical descendants of Abraham.

children of God

This refers to people who are the spiritual descendants who have faith in Jesus.

children of the promise

This refers to people who will inherit the promise.

a son will be given to Sarah

AT: "I will give Sara a son" (See: rc://en/ta/man/translate/figs-activepassive)