But far greater was the stream of influence from the Jewish and Christian sacred books. In the Old Testament stood various texts condemning usury—the term usury meaning any taking of interest: the law of Moses, while it allowed usury in dealing with strangers, forbade it in dealing with Jews.
In the New Testament, in the Sermon on the Mount, as given by St. Luke, stood the text “Lend, hoping for nothing again.” These texts seemed to harmonize with the most beautiful characteristic of primitive Christianity; its tender care for the poor and oppressed: hence we find, from the earliest period, the whole weight of the Church brought to bear against the taking of interest for money…
This unanimity of the fathers of the Church brought about a crystallization of hostility to interest-bearing loans into numberless decrees of popes and councils and kings and legislatures throughout Christendom during more than fifteen hundred years, and the canon law was shaped in accordance with these. At first these were more especially directed against the clergy, but we soon find them extending to the laity.
White, A.D. (1895). A History of the Warfare of Science with Theology in Christendom. Available http://abob.libs.uga.edu/bobk/whites01.html. Last accessed 25th Dec 2015.