From the Ashoka course The Story of Zen
Mazu's uncompromising methods foreshadowed those of Linji. While there is little in the way of written record of Mazu's teachings, Zen lore celebrates Mazu's methods and the awesome sense of presence that he conveyed. This comportment (remarkable composure, effortless grace and uncluttered vision they embody) is conveyed powerfully in the legends that come down to us.
Mazu simplified the idea of what constitutes enlightenment, stressing the immediacy of enlightenment. As he defined it, "seeing into one's own nature" simply meant understanding (intuitively, not rationally) who you are and what you are. This truth could be taught with whatever method seemed appropriate at a given moment.
Mazu's Chan seems merely so many ways of finding out who you are and what you are.
For instance, although he was familiar with the great Mahayana sutras, Mazu never mentioned Huineng or the Diamond Sutra. His Chan, expressed in simple everyday language, seems merely so many ways of finding out who you are and what you are. Furthermore, there seems to be nothing specifically that you can do to accelerate the occurrence of sudden enlightenment, other than use traditional practices to make your psyche as uncomplicated as possible and then wait for the moment to strike (he, of course, experimented to find ways to accelerate the arrival of that moment).
But he had nothing encouraging to say about the effectiveness of meditation as an aid to finding the desired non-rational insight, which he sometimes described using the borrowed term "Tao":
The grasping of the Truth is the function of everyday-mindedness. Everyday-mindedness is free from intentional action, free from concepts of right-and wrong; taking and giving, the finite or the infinite . . . . All our daily activities—walking, standing, sitting, lying down—all response to situations, our dealings with circumstances as they arise: all this is Tao.
Mazu's real immortality derives from his contribution to the arsenal of methods for shocking novices into enlightenment, methods still found in Zen today. Mazu apparently was the first master who developed non-meditative tricks for nudging a disciple into the state of "no-thought." He was an experimenter, and he pioneered a number of methods that later were perfected by his followers and the descendants of his followers.
He was the first master to ask a novice an unanswerable question, and then while the person struggled for an answer, to shout in his ear (he liked the syllable "Ho!") hoping to jolt the pupil into a non-dualistic mind state. Another similar technique was to call out someone's name just as the person was leaving the room, a surprise that seemed to bring the person up short and cause him to suddenly experience his original nature. A similar device was to deliver the student a sharp blow as he pondered a point, using violence to focus his attention completely on reality and abort ratiocination.
Anecdotes and exchanges
Mazu's Chan community was the incubator for the greatest thinkers of the eighth century and the setting for some of the finest Chan anecdotes.
The anecdote is the perfect Chan teaching device, since it forces the listener to find its meaning in his own inner experience. The sermon provided the theoretical basis for an idea, but the anecdote showed the theory in action and made the listener share in a real experience, if only vicariously.
These two anecdotes were later enshrined in the famous collection of koans called the Wumen Kuan (Japanese: Mumonkan):
Question: "What is Buddha?" (What is the spirituality that all seek? )
Mazu: "Mind is Buddha"
Question: "What is Buddha?"
Mazu: "No mind, no Buddha" (Spirituality is in the mind, and for its realization one must realize the mind.)
In both instances Mazu is merely following the earlier idea that there is no reality and thus no enlightenment outside the mind.
Mazu discovered and refined what seems to have eluded earlier teachers such as Huineng and Huairang—namely, a trigger mechanism for sudden enlightenment. He originated the use of shouting and blows to precipitate enlightenment, techniques to become celebrated in later decades in the hands of men such as Huangbo and Linji, masters who shaped the Rinzai sect.
From the Ashoka online course The Story of Zen