Ancient buddhas say:
Not doing evils,
devoutly practicing every good,
purifying one's own mind:
this is the teachings of all buddhas.
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In the above quotation the term "evils" refers to [what is called] morally evil among the categories of morally good, morally evil, and morally undefined. Its moral nature, however, is uncreated. The natures of morally good and morally undefined likewise are uncreated. They are untainted, they are the real aspects, which is to say that these three categories of moral nature encompass manifold varieties of dharmas ...
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It is not that evils do not exist, but that there is only "not doing." It is not that evils do exist, but that there is only "not doing." Evils are not emptiness; it is "not doing." Evils are not form; it is "not doing." Evils are not "not doing," for there is only "not doing." For example, spring pines are neither non-existent nor existent; they just are not done. Autumn chrysanthemums are neither existent nor are they non-existent; they just are not done. The buddhas are neither existent nor non-existent; they are "not doing." Pillars, lamps, candles, whisks, staffs, and so forth, are neither existent nor non-existent; they are "not doing." One's own self is neither existent nor non-existent; it is "not doing."
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Because this is so, to act on the assumption that "if [evil already] is 'not doing,' then I can just do as I please" would be exactly as [mistaken as] walking north while expecting to arrive in [the south].
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Every good is not existent, is not non-existent, is not form, is not emptiness, nor anything else; it only is devoutly practicing. Wherever it fully appears, whenever it fully appears, it must be devoutly practicing. In this devoutly practicing, every good will certainly fully appear. The full appearance of devoutly practicing is itself the kôan, but it is not production and destruction, it is not casual conditions.
The same is true regarding the entering, abiding, and departing of devoutly practicing. Devoutly practicing even one good among the every good causes the entirety of dharmas, the whole body, and reality itself to devoutly practice together.
http://scbs.stanford.edu/sztp3/translat ... ation.html