Yangshan asked Guishan, "What is the true abode of the Buddha?"
Guishan said: "Think of the unfathomable mystery and return your mind to the inexhaustible numinous light. When thoughts are exhausted you arrive at the source, where true nature is revealed as eternally abiding. In that place there is no difference between affairs and principle, and the true Buddha is manifested."
Upon hearing these words, Yangshan experienced great enlightenment.