|Page from the original Mumonkan|
Chu summons his attendant who always responds. There is an element here akin to what was covered in Koan 16, When the Bell Tolls (see entry: http://zenthrowdown.blogspot.com/2011/05/mumonkan-koan-16-when-bell-tolls.html). This is about how we deal with external stimuli.
Chu is wondering whether he is betraying his attendant by summoning him and placing him in the position of responding to a stimuli just like the bell in koan 16. He is revealing his attendant's response to such stimuli. This is poor training for his attendant.
However Chu realizes that, in fact, it is he who is wrong-minded not his attendant. It is he who is initiating the entire stimulus. We also do not know his reasoning for summoning the attendant, but the fact that he has to do it three times suggests a lack of focus or clarity. Why not summon him one time for what is needed? Why summon him at all? Why have an attendant to summon?
In truth, the attendant's responsiveness betrays Chu by revealing his expectation of a response. The attendant's faithfulness encourages Chu in this reliance, and he initiates it over and over. While an attendant could practice everyday Zen in his duties, the person who summons is unlikely to be in the correct mindset. Rather than practicing everyday Zen or sitting in zazen, they are summoning or interacting or needful of the world around them (i.e., wrong-minded).
After I had my solution, I read Mumon's verse and notes and feel like I reacted to this in somewhat the same way he did. His verse here was:
"He carried an iron yoke with no hole
And left a curse to trouble his descendants
If you want to hold up the gates and doors
You must climb a mountain of swords with bare feet"
A yoke is obviously a form of imprisonment, but a yoke with no hole would be imprisonment not by prison bars, fetters, or a yoke on your neck. Instead, you are imprisoned by a burden you carry (a wrong way of thinking). If you want to attain enlightenment (line 3), do it yourself. Better to be yoked in fact and labor than to carry a pointless burden to no end. The former allows for the possibility right mindedness, the latter can only be delusion.