It is quite clear from The Prologue that Geoffrey Chaucer did not think very much of the clergy. He does not have much of a good word for any of the clergy members with the exception of the Parson.
In general, he points out that the clergy members are not really acting as they are supposed to. He mentions how well they seem to live. They go out hunting, for example, or they forget about their vows of celibacy. They dress in rich clothes and eat delicacies instead of living lives of poverty.
By contrast, the Parson lives the way clergy are supposed to. He puts the needs of his flock before his own and, as Chaucer says, he preaches the Gospel but lives it first.