Shundo David Haye

'Xuefeng asked a monk, "Where are you going?"
The monk said, "I'm going to do community work."
Xuefeng said, "Go."

Yunmen said, "Xuefeng understands people according to their words."
Hongzhi said [about this dialogue], "Don't move. If you move I'll give you thirty blows. Why is this so? For a luminous jewel without flaw, if you carve a pattern its virtue is lost."'

This is a classic example of a koan illustrating non-abiding. Both answers are perfect, but you cannot stick to either.