The Pardoner's Tale, from Geoffrey Chaucer's "Canterbury Tales," shows the reader that the Pardoner is not only corrupt but proud of the moral depths which he has reached. He has come to love the comforts that come from the money he charges for pardoning the sins of others.
During the Middle Ages, a pardoner was a layperson or clergyman whose job was to travel around raising money for the Church by granting indulgences, or pardons for previous sins, from the Pope to contributors. As one might imagine, there was a lot of room for corruption in this sort of business.
The Pardoner is quite open about his hypocritical life as he tells his tale to the rest of the traveling pilgrims. He goes through a rant against such sins as swearing, drinking, gambling and eating to excess, but right after he gives his "official" position against swearing, he swears before beginning the main part of his story.
Even though the Pardoner had already told his fellow travelers that his relics were fakes, his storytelling habits take over, and he pulls out his wares. He offers the first chance to kiss the relics to the Host, pointing out that the sin in the Host's life was clearly the greatest. This boldness after all of his hypocrisy shows the moral depths to which the Pardoner has descended.