Usury

Usury at one time was widely recognized to mean any increase on a loan, whether it was money or property. If the loaned item was being returned, yet there was somethig additional coming back as well, that was the "increase" and therefore usurious.

Near the end of the middle ages, government acting on behalf of the rich elites, brought about the idea of interest as a separate legal consteuct from usury. They started making it apply solely to money and it was now sanctioned by civil law. Usury was still around, just as it is today, but the interest was used to mean acceptable increase, whereas usury was for unacceptable increase.

Morality isn't determined by government, so how a society views an increase on a loan is based on things beyond the reach of government.