The Canterbury Tales: The Wife of Bath's Tale Lines 1131-1170 Summary
(The hag continues her response to her husband's complaint:)
Dante speaks rightly when he says that one rarely inherits worth from one's family tree because God wants us to owe our gentility to him.
From our parentage we can claim only temporal, material things, which may be destroyed or taken away from us by other men.
Here's another reason gentility cannot possibly be a result of parentage: if gentility were the natural result of a certain ancestry, then people of this ancestry would never cease to act gently. Whether privately or in public, they would never be able to commit evil acts.
Take fire into the darkest house anywhere and let men shut the doors and go away from it; even so, the fire will continue to burn just as brightly as it does when twenty thousand people are watching it. It is always true to its nature, until it dies.
From this, you can see how gentility is not the result of lineage. Since people of high lineage do not always act in accordance with gentility, it can't be something that's natural to their kind in the same way that brightness is natural to the fire.
God knows, it's always possible to find a lord's son who commits villainous acts yet prizes his 'gentility' because he comes from a noble lineage and virtuous ancestors.
He is not a gentleman, whether he's a duke or an earl, because villainous deeds make him a churl.
Gentility is not just the renown of your ancestors; that actually has nothing to do with who you are as a person.
Your gentility comes from God.
Therefore, gentility is a result of grace, not ancestry.