The Pardoner tells a tale about avarice. Three young men seek Death and find gold under a tree. Each of them wants the gold for himself. The youngest has to go to town to bring some food and wine; the other two plot to kill him and share his part of the gold, but he has the same plan for them - he is going to poison their wine. When he arrives, they kill him indeed, but still drink his wine, which gets them killed. So, all three men manage to meet Death, guided by their avarice.
By telling this tale, the Pardoner doesn't want to hide his intentions - to trick people into giving him money. He openly admits that he is after their money, and will do everything necessary to make them pay for the false relics and the indulgences. His main message is that money is the root of all evil. So, even though he is greedy, it is still a sin that needs to be absolved. The Pardoner is a cunning person who relies on the power of stories to make people act in a certain way. People are afraid of the Last Judgment, and he knows that. People will pay for pardon, even though they know that they are paying to the sinner. He knows and takes advantage of that fact.
