佛果圜悟禪師碧巖錄 9.47

9.47

[90] Case: A monk asked Zhimen, "What is the substance of prajñā?" (The entire body has no image. It cuts off the tongues of everyone under heaven. What use is substance?)
Zhimen said, "The clam holds the bright moon." (Swallowing the myriad forms with light—let that rest. What about the true eye at the head of the staff? The crooked does not conceal the straight. Adding another layer of frost on top of snow.)
The monk asked, "What is the function of prajñā?" (Falling back three thousand li. What do you need function for?)
Zhimen said, "The rabbit conceives." (Steep! The bitter gourd is bitter right to its root; the sweet melon is sweet all the way through its stem. Making a living within light and shadow. He does not leave Zhimen's burrow. If someone were to step forth, tell me, is it the substance of prajñā or the function of prajñā? For now, add mud on top of dirt.)