Admissions officers, in their own ways, stand as guardians over the principles of fairness and openness, and the university derives prestige from its store of moral credibility. Making deals to sell that credibility can be dangerous. In the Middle Ages, Catholic clergy conceived of themselves as selling beneficence from an infinite "treasury" of holiness; they used the money from the indulgences they sold to build hospitals, churches, and leper colonies. But the system got out of control (as one sixteenth-century preacher famously put it, "As soon as money in the coffer rings, the soul from purgatory's fire springs"), and had to be Reformed.