Religion in "The Miller's Tale" seems mainly to be something characters use and abuse in order to get what they want. Absolon forgoes piety for attention when he takes a role in the local miracle play in hopes of attracting Alisoun. Nicholas uses the Biblical story of Noah and the flood, and a false piety, to set John up so he can frolic with Alisoun undisturbed. And then, of course, there's the whole obscene religious allegory and symbolism in the story: the huge "Goddes pryvetee," or genitals, John hangs from his roof; the fart of thunder and cry of water that could allegorize Noah's flood; and the way in which Nicholas's God-role and John's fall play on the Fall of Man. As is true with love, the only character who seems to truly have faith in this tale (John) suffers for it in the end, appearing highly ridiculous. All of this adds up to a highly irreligious take on religion in "The Miller's Tale."
"The Miller's Tale" portrays religious piety, like love, as something only fools indulge in.
The ending of "The Miller's Tale" is meant as an allegory of the Fall of Man.
The ending of "The Miller's Tale" does not work as an allegory of the Fall of Man.