The Case
The wind was flapping a temple flag, and two monks started an argument. One said the flag moved, the other said the wind moved; they argued back and forth but could not reach a conclusion. The Sixth Patriarch said, "It is not the wind that moves, it is not the flag that moves; it is your mind that moves." The two monks were awe-struck.
Mumon's Comment
It is not the wind that moves; it is not the flag that moves; it is not the mind that moves. How do you see the patriarch? If you come to understand this matter deeply, you will see at the two monks got gold when buying iron. The patriarch could not withhold his compassion and courted disgrace.
Verse
Wind, flag, mind moving, All equally to blame. Only knowing how to open his mouth, Unaware of his fault in talking.