A monk asked Kegon, “How does an enlightened one return to the ordinary world?” Kegon replied, “A broken mirror never reflects again; fallen flowers never go back to the old branches.”
Zen joke from: Lighter Side of Zen Buddhism:
Q: What did one Zen practitioner give to another for his/her birthday?
A: Nothing.
Q: What did the birthday boy/girl respond in return?
A: You are thoughtless for giving me this meaningless gift.
To which the giver replied, “Thank you.”