Geoffrey Chaucer was a man with strong opinions. He had a great deal to say about religion: either in criticism of many members of the organized church at that time, or in praise of others (presented as members of the pilgrimage in The Canterbury Tales) who exemplified a life guided by piety, spirituality and/or morality.
There are several characters in Chaucer's tale with whom the writer found a great deal to criticize. These characters were all "employed" in some fashion by the Church. Those who stand out are the Pardoner, the Friar and the Monk. These are men more interested in money, entertainment and women, than in the members of the parish who need their help. These men have found a way to bilk their "flock" out of a great deal, and all of their actions are contrary to the teachings of the Church.
For example, "men of the cloth" (though who were employed by the Roman Catholic Church) were supposed to give up their worldly goods. The Monk cares not for his congregation or the teachings of the Church, but how he loves to hunt:
Therefore he hunted hard and with delight;
Greyhounds he had as swift as birds in flight;
To gallop with the hounds and hunt the hare
He made his joy, and no expense would spare. (189-192)
There is also the Friar. He gives forgiveness and redemption—for a price:
He had been licensed by the Pope's own hand!
Full sweetly would he listen to confession,
And very pleasantly absolved transgression;
He could give easy penance if he knew
There would be recompense in revenue... (220-224)
The last of the clergy that Chaucer so criticizes is the Pardoner. This is a man who is supposed to help his flock, traveling with special permission from one shire to the next. He sells pardons to people that have the Papal seal, but are stolen. He has "souvenirs" he also sells:
For in his bag he kept a pillowcase
That was, he said, our Blessed Lady's veil;
He claimed to own the fragment of the sail
That Peter had the time he walked on the sea... (522-525)
With these false "relics," the Pardoner can make more in one day than a parson (another holy man) would make in a month or two! To get a clearer sense of how crooked Chaucer saw them to be, it is important to compare them to the Parson. The Parson does all he can for his congregation, and we can infer that Chaucer greatly admires this "man of the cloth."
He would not make an excommunication
For tithes unpaid, but rather would he give—
Helping his poor parishoners to live—
From the offerings or his own small property. (381-385)
This is a man who loves his "flock" more than anything he might own. He was a man known for his good deeds. Chaucer notes:
No better priest doth anywhere reside.
There are a number of people in the story, also, who were very pious, though they are not men (or women) of God. The Knight is a man who has fought in the Crusades (for God)...
...loved the way of chivalry,
Honor and faith and generosity. (45-46)
Upon his return, his first inclination is to go on this pilgrimage to pay homage to God:
For he was lately come from his voyage,
And went at once to do his pilgrimage. (77-78)
By reading between the lines and comparing—not only those who serve the Church, with each other, but with the "common" man who serves God in his daily life.
Chaucer admires those who serve others through their faith (as the Parson), as well as the Knight who respects God in his daily life. He is especially displeased with the religious hypocrites.