en_tn/rom/04/13.md

heirs

The people to whom God has made promises are spoken of as if they were to inherit property and wealth from a family member. (See: rc://en/ta/man/translate/figs-metaphor)

but through the righteousness of faith

The words "the promise came" are understood from the first phrase. You can translate this by adding these implied words. AT: "but the promise came through faith, which God considers as righteousness" (See: rc://en/ta/man/translate/figs-ellipsis)

if those who live by the law are to be the heirs

Here "live by the law" refers to obeying the law. AT: "if those who obey the law are the ones who will inherit the earth" (See: rc://en/ta/man/translate/figs-explicit)

faith is made empty, and the promise is void

"faith has no value, and the promise is meaningless"

there is no trespass

This can be restated to remove the abstract noun "trespass." AT: "no one can break the law" or "it is impossible to disobey the law" (See: rc://en/ta/man/translate/figs-abstractnouns)