This chapter analyzes the practice and discourse of Jewish moneylending in the Holy Roman Empire between the late fifteenth and early seventeenth centuries. Usury, as defined in the Old Testament was the taking of interest on loans to one's brethren; Jewish usury, as defined by the Christian polemic of the late Middle Ages, referred to the excessive taking of interest on loans made by Jews to Christians. The key word was “excessive,” and it denoted the intermingling of economic and moral thinking in this anti- Jewish discourse. Usury was a form of immorality. According to the pamphlet, A Faithful Warning to all good-hearted Christians, published in 1531 by a certain Anthony B., German Jews took excessive interest (überschwencklicher Wucher) because, “as almost everyone knows, the Jews go around cheating from youth to old age.” The pamphlet provides a table of usurious interest to show that a debt of 1 Frankfurt gulden would, in twenty years, accumulate almost 2,593 florins in interest. The pamphleteer urged Christians to help one another with interest-free loans, in order that Christian communities might remain pure and uncontaminated.