"Virtue is its own reward."
What the hell does that mean?
I guess, if I had to take a swing at it, I would say that it points to the difference between ethics and morality. Ethics are public statements, open to the applause or catcalls of those observing them. Morality is what is practiced when nobody is looking ... not even the practitioner.
A tennis player does not "play tennis" -- s/he just plays tennis. Delight and despair are fifth wheels on the moment at hand.
Maybe virtue is what exists before "virtue" and "reward" are invented.