Thesis- Geoffrey Chaucer's "The Wife of Bath" shows that a wife having equal possesion of mastery in her marriage is best for both man and women....

The Wife of Bath is quite a character. Of all the characters in Geoffrey Chaucer's Canterbury Tales, she is probably the most memorable. What makes the Wife so memorable is her brash manner. She is so outspoken that she would probably be considered controversial even today, so imagine the impression she must have made on her Medieval audience. 

The quote you are referencing occurs in the Wife's prologue, not in her actual tale to...

The Wife of Bath is quite a character. Of all the characters in Geoffrey Chaucer's Canterbury Tales, she is probably the most memorable. What makes the Wife so memorable is her brash manner. She is so outspoken that she would probably be considered controversial even today, so imagine the impression she must have made on her Medieval audience. 

The quote you are referencing occurs in the Wife's prologue, not in her actual tale to the pilgrims. In that prologue (not to be confused with the General Prologue that actually comes at the beginning of the book--before the Knight's Tale), the Wife gives her opinions on marriage and sex and then describes her relationships with her many husbands.

The husband she is referring to in this quote had previously hit the Wife on the ear hard enough to permanently impair her hearing. He did this out of frustration with his wife, who simply would not behave as he wanted her too. His attempt for force her to act like a woman of that time period was supposed to act backfired when he saw how badly he had hurt her. At that point, he uttered the quote you referenced in your question, apparently out of remorse. It appears to have succeeded in improving their relationship, for the Wife said:

. . . after that day we never argued.

So God help me, I was as kind to him 

as any wife from Denmark to India,

and as true, and so was he to me.