“It is foolish to use the verb “to appear” in describing the manifestation of the buddhas. We simply use the expression “a buddha appears in the world” to make it easier for sentient beings to understand. “Picks up a shit pail and hauls away all the shit of conceptual proliferation” means that a buddha removes all traces of various types of ignorant thoughts. If you do not depart from the original true reality of the middle way, then whatever words you say will be like “hauling away shit.”
From “A bird in flight leaves no trace, the teachings of Huangbo”.