When Gotham is ashes, then you have my permission to die.

Bruce Wayne: Why didn’t you just kill me?
Bane: Your punishment must be more severe.
Bruce Wayne: Torture?
Bane: Yes, but not of the body. Of the soul. I will build you and Gotham up with hope and then destroy you. Hope is really the key to torture. Gotham will build to a point of joy and then be wiped from the map.
Bruce Wayne: You are a madman.
Bane: When Gotham is ashes, then you have my permission to die.