The famous story of Chanticleer and Pertelote has a clear message to it, which is particularly heightened when we remember the person who is telling the tale. Chanticleer is shown to be a creature that is easily beguiled by the words of Pertelote, and in particular her rebuke about the seriousness with which he takes his dream:
"Alas!" cried she. "For, by the Lord above,
Now you have lost my heart, lost all my love.
I cannot love a coward, that I swear!"
It is his love for her that causes Chanticleer to go against his better judgement and leads to his near escape with the fox. Thus the message of this tale, apart from the danger of succumbing to flattery, perhaps can be said to concern the dangers of heeding the advice of women. This is not particularly politically correct in today's world, but we need to remember that this was an immensely popular medieval theme, focusing on Eve as the archetype of the woman as temptress. Women were viewed as "the weaker sex" and thus offered foolish and dangerous advice.
Let us think about why it is that the Nun's Priest tells the tale. His role is a servant to the Prioress. From what we have seen of her, she is depicted as rather foolish and overly sentimental. His work dictates that he must live surrounded by women who are working under her, and thus perhaps share her failings. Thus we can see this tale as a barbed attack against his mistress and also against the women by which he is surrounded.