How were the Jews and the Catholic Church able to work together in medieval times?
The Church needed the Jews to handle their finances (since they were forbidden from lending money at interest, considering it usury). The Jews did not “need” the Catholic Church, but were willing to help out. Unfortunately, because the Jews were “different” with their secret language and different holy book and wierd dietary habits, and because they refused to become good catholics, and because they were able to do business in a more modern fashion and therefore accumulated wealth, it periodically occurred to the Church that represssion and persecution would be advantageous in saving their souls and filling the coffers of the Church. There is a fable ablout “Killing the goose that lays the golden egg” that comes from this period and may have been directed at those who thought that longterm wealth could be stolen.
