'Debt' in the Bible

I have a duty to perform and a debt to pay both to Greeks and to barbarians [the cultured and the uncultured], both to the wise and to the foolish.

Now to him that worketh is the reward not reckoned of grace, but of debt.

So then, my brothers, we are in debt, not to the flesh to be living in the way of the flesh:

Owe nothing to anyone except to love and seek the best for one another; for he who [unselfishly] loves his neighbor has fulfilled the [essence of the] law [relating to one’s fellowman].

They were pleased to do it, and they are indebted to them. For if the Gentiles have come to share in their spiritual things, then they are indebted to serve them also in [tangible] material things.

Who for my life put their necks in danger; to whom not only I but all the churches of the Gentiles are in debt: