A specialist in Catholic social doctrine, Miller A., argues, circa 1994, that "the words 'bank' and 'banking' are almost nonexistent in the documents of modern Catholic social teaching. Perhaps because the medieval teaching was never formally retracted that money was unproductive and therefore money lending at interest was therefore immoral, yet the church itself became an active investor... Or perhaps it was because the church was deeply involved in financial matters at the highest levels that it was in no position to criticise."