Some points regarding humor in The Nun's Priest's Tale by Chaucer:
Humor and Distance: Chaucer's language is "far" from us in several senses: it is temporally far removed from our time, its spelling and vocabulary are far from what we're used to, and it is meant for a culture that is far from our own in a few ways. This distance makes it a little harder to enjoy Chaucer's humor. One has to work through a few levels of difficulty and misunderstanding before one can see the joke, and by then the timing is all off and the effect may be diminished. A part of being receptive to humor is being at ease, being relaxed and in the mood to enjoy rather than work on tasks of literary understanding. Today it is difficult for anyone but experts to read Chaucer with the fluency that the most effective humor would require.
Presaging Dickens: The beginning of the prologue presages the theme repeated so often by Dickens: a poor boy getting lucky and becoming rich and honored. Here is how the knight says it:
"And the contrarie is joye and greet solas,
As whan a man hath been in povre estaat,
And clymbeth up, and wexeth fortunat,
And there abideth in prosperitee.
Swich thyng is gladsom, as it thynketh me,
And of swich thyng were goodly for to telle."