He is intimating, a manly man who is ful fat and in good point, which suggests of his luxury lifestyle. The narrator is obviously intimidated by him saying And I seyed his opinion was good implying that he was afraid to oppose him and therefore indicating that the monk appears to be a man capable of standing up for himself to quite an extent, hence silencing others, who dont want to test this capability! The image of an aggressive and imposing figure does not go hand in hand with that of a monk. Indeed, the narrator states ; his eyen stepe, and rollinge in his head, that stemed as a forney of a leed. This imagery also suggests a devil-like connotation that is clearly hyperbole, but must have had a great effect on the narrator for him to use it.
The sense of the varied Medevil society in trios vocation is only suble, i.e. the first stays in a convent, anther preaches about God and the last one can take confession. But where the sense of variet is more evident is in the fact that the extent to which they mix up, or rather become confused between their duty to god and their love of the more material world and its pleasures. Here the main contrast between the characters is the strength of criticism.
I.e. The prioress only receives slight criticisms of minor faults but on the whole it is delivered with affection and used to poke fun at her. But the portrait of the Friar presents us with a cynically ironic view on the way that the smarmy, sly and selfish villain works. Also, the trios priorites for God become less pronounced as we move down the list of portraits. The prioress seems to think of herself as a courtly romantic saviour, but it is presented as a cute little nuance, and the monk who would rather be having fun than doing boring jobs that will turn him wood. But the reader feels that it is understandable and rather a humane reaction. But the Friar is positively working against God and defeating society.