Master Dongshan (Jap.: Tozan) had this exchange with Master Yunyen (Ungan). It involves a Hossu, the horsehair fly swatter or whisk, one of the traditional implements of a Zen Teacher ...
Dongshan asked, "What sort of person is able to hear the Dharma expounded by insentient beings?"
Yunyen said, "Insentient beings are able to hear it."
"Can you hear it, Master?" asked Dongshan.
Yunyen replied, "If I could hear it, then you would not be able to hear the Dharma that I teach."
"Why can't I hear it?" asked Dongshan.
Yunyen raised his fly whisk and said, "Can you hear it yet?"
Dongshan replied, "No, I can't."
Yunyen said, "You can't even hear when I expound the Dharma. How do you expect to hear when insentient beings expound the Dharma?"
Dongshan then asked what sutra teaches that insentients expound the Dharma, and Yunyen said that the Amitabha Sutra states, "Water, birds, tree groves, all without exception recite the Buddha's name, recite the Dharma."
We see in the past that those who transcended the ordinary and transcended the sacred and those who died while sitting or died while standing, relied totally on this power. Moreover, changing of the moment through the action of a finger, a [flag]pole, a needle, or a wooden clapper; and exact experience of the state through the manifestation of a whisk, a fist, a staff, or a shout, can never be understood by thinking and discrimination. How could they be known through mystical powers or practice and experience? They may be dignified behavior beyond sound and form. How could they be anything other than criteria that precede knowing and seeing? [Nishijima]
In surveying the past, we find that transcendence of both mundane and sacred and dying while either sitting or standing have all depended entirely on the power of zazen. In addition, triggering awakening with a finger, a banner, a needle, or a mallet, and effecting realization with a whisk, a fist, a staff, or a shout-these cannot be understood by discriminative thinking; much less can they be known through the practice of supernatural power. They must represent conduct beyond seeing and hearing. Are they not a standard prior to knowledge and views? [SZTP]
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