I thought the Pardoner's prologue and tale we're a great example of Chaucer's humor. The two tales were a joke told in reverse. The Pardoner, a man charged with giving forgiveness for sins, uses the prologue to proclaim how he engages in the deadly sins.  Pride-For Certes many a predicaioun comth ofte time of ivel entencioun, som for plesance of folk and flaterye, (404-408)

Wrath-Thus quyte I folk that doon us dispesances, thus spitte I out my venym under hewe, Of hoolynesse, to semen hooly and trewe (413) 

Lust (lines 453) 

Sloth 444-446

Gluttony-452

 Then the actual tale is one that shows the hypocrisy by which the Pardoner lives.  While I ask of forgiveness of Foucalt and any that cringe at the mention of biography, I cannot help but wonder how much anti-indulgences sentiment was apparent at the time of Chaucer's writing. While this work predates Martin Luther, I can only assume that the sentiments against the practice of indulgences was present at the time. (?)