Now the great radiant mantra. Without a speck of dust, bright like a mirror, the state of ultimate Emptiness reflects everything. A mirror leaves nothing unreflected. If a beggar comes it reflects a beggar, if a nobleman, then the noble. Whatever the form it reflects it, and this accommodation to any form is what is termed the bright mirror.
Long ago Zen master Seppo asked: ‘What if you suddenly come upon a mirror?’ To which his disciple Gensha replied: ‘Into a hundred fragments!’ Smash it to pieces was his reply. For while the heart is caught by something called a bright mirror; it is no real mirror, no mirror at all.
It happened a little time ago that a cabinet minister resigned, and he spoke of himself in the Chinese phrase: ‘Bright mirror, still water.’ Perhaps you will remember the incident. The meaning was that his heart was unmoved, that he felt like a mirror without a trace of clouding. It was like stilled water without a fleck on it, with no disturbance. That was what he seemed to be saying, but if all he meant was the bright mirror of stilled water, we may feel there was yet something lacking.
Isn’t there something yet lacking in a man when he says he is a bright mirror in still water? If that is the sort of bright mirror and still water, then—into a hundred fragments! Until it is smashed up altogether it is no real bright mirror. This point may be a little difficult to appreciate. When it is done, each fragment must itself be a mirror. The tiniest sliver must be a mirror. In truth our bright mirrors have to become a hundred fragments.
What is this smashing? A master of our line warns us that the bright mirror is not water stopping still, but water breaking into thousands of drops and flowing on, adapting to any form that comes. Such is the bright mirror. To rescue one who has fallen into the mud, the Bodhisattva goes and himself becomes muddied. To save a drowning man he leaps into the water and rescues him by himself becoming wet. This is the breaking of the mirror into fragments.
For the sake of the people, the brilliant mirror of the wisdom of ultimate Emptiness is broken up into their hearts and comes to reflect everything there. It is not simply resting satisfied with being oneself a mirror. This is a point of profound significance.
Than such action there is no higher power, to it there is nothing comparable, and so it is peerless and unequalled. It sweeps away all suffering, suffering of any living being and under any circumstances. Here let us consider the pain of life and death as the type of all other pain. The Prajna Paramita is the power which releases from the suffering of the round of birth-and-death. The holy words of the Buddha never prove false, so say the Lotus Sutra and the Diamond Sutra. The Buddha’s words are not like our talk, of which it hardly matters whether it is said or left unsaid, which is just to pass the time. He is not expressing, like us, some attitude which is fundamentally pointless. Nor is he speaking of abstractions. His every phrase, every word, has a sublime power to release beings from all sufferings, to free from life and death.
Now Master Dogen tells us: ‘Know that merely understanding oneself to be Buddha is not knowing the Buddha way. ’ A mere comprehension of the proposition that all are Buddhas, of the truth that one is oneself Buddha, to say ‘I understand it,’ is not the same as knowing the Buddha way.
Simply to have that understanding of the truth is not to be released from birth-and-death. When they speak of the words of the Buddha having the power to release, it does not mean just by an intellectual understanding. The true words of the Buddha are those which all beings from illusion and pain by enlightenment in them It is not a question of intellect, it is not a question of saying ‘I understand’. Buddhism does not say to the intellect: ‘You are Buddhas—have you understood it?’ The true words have to be powerful to release from all sufferings, and those alone are the truth-bearing words of the Buddhas and patriarchs.
by Abbot Obora of the Soto Zen sect
See also Prajna Paramita Sutra: English version with commentary