Grace

Favour given to someone who did nothing to earn it — and cannot pay it back.

In common Greek, cháris was a patron's favour to a client, and it carried the duty of returning it. Paul takes the word and breaks precisely that part: here the favour is unearned and the debt unpayable, which dismantles any exchange. The Hebrew equivalent, chen, already appears with Noah, who “found grace in the eyes of the Lord”, before any merit is mentioned.