Explanation of the Diamond Sutra: Why Does the Tathāgata Have No Fixed Dharma to Speak?

When the Buddha taught the Dharma in the world, He always taught in accordance with causes and conditions. The Buddha observed the conditions of sentient beings—whatever the condition, that was the Dharma He taught, expounding the Dharma according to beings' spiritual faculties (indriya). At the very beginning after the Buddha's attainment of enlightenment, He first taught the Huayan Sutra in the various heavens, delivering the great bodhisattva disciples who had followed Him in cultivation across countless kalpas, while the śrāvaka disciples of the Sahā world were as if deaf and mute. The Buddha then returned to the human world to teach the Hinayana Āgama sutras to the śrāvaka disciples seeking liberation, so that they could achieve results in their cultivation, and then turn back to study and practice the Mahāyāna Dharma. Because the sentient beings of the Sahā world have shallow faculties and all seek liberation, wishing to leave suffering and attain bliss, the Buddha taught the Dharma of the three vehicles in the Sahā world.

In other Buddha-lands, however, the Buddha taught only the one vehicle—the Dharma of the One Buddha Vehicle—delivering sentient beings of bodhisattva disposition to accomplish the Buddha Way. Whenever the Buddha taught the Dharma, He always relied on a condition: when an event or phenomenon appeared, the Buddha would teach a Dharma corresponding to it; sometimes disciples would ask questions. There was always a premise before a Dharma was taught. Dharma taught without any cause or condition was extremely rare—that was for Dharma of particular importance, yet it too matched the capacities of sentient beings. Thus the Buddha's teaching of Dharma was never fixed; Dharma arises from causes and conditions and is not fixed. All Dharma, no matter in which Buddha-land it was taught, serves to remedy sentient beings' illness of ignorance and illness of foolishness—whatever ignorance there is, that is the Dharma the Buddha teaches; when ignorance is completely extinguished, the Dharma is no longer of use. Therefore the Buddha's Dharma is like a raft used to cross a river—once one reaches the shore, it is abandoned.

Since Dharma exists in dependence on causes and conditions, it is illusory and empty, to be used for a time and then discarded; therefore one must not cling to it as real. Yet while ignorance still remains, one must hold on to it and use it as a tool. For example, with the Dharma of the Four Noble Truths, once one has realized the fruits and attained liberation, this Dharma is of no more use to the arhat; then one cultivates as a pratyekabuddha the Dharma of the twelve links of dependent origination. After attaining the fruit of a pratyekabuddha, the Dharma of dependent origination is also of no more use, and one needs to cultivate the bodhisattva's six perfections. After seeing the mind and realizing one's nature, the six perfections of the outer gate are of no more use, and one cultivates the six perfections of the inner gate, entering the first bhūmi. After attaining the bhūmis, the six perfections of the inner gate are of no more use, and one cultivates the ten pāramitās. After becoming a tenth-bhūmi bodhisattva, the ten pāramitās must also be abandoned. After cultivating the Dharma of equal enlightenment and wondrous enlightenment to perfect the Buddha Way, all Dharma is no longer needed—everything is abandoned, and the mind is empty, without any Dharma.

Only because all Dharma has been perfectly cultivated can one, after becoming a Buddha, proclaim it for sentient beings. Therefore all the Dharma spoken by the Tathāgata is not Dharma that originally existed and is fixed and unchanging; it is all empty, not real Dharma. But neither is it not real Dharma, because sentient beings, relying on this Dharma, can realize the true Dharma, the unconditioned Dharma; moreover, when the Buddha proclaimed this Dharma, He never departed from the true tathatā Dharma—it was precisely the tathatā Dharma functioning here that enabled the Buddha to proclaim it. All this Dharma comes from the Buddha's own mind's tathatā, flowing forth from within tathatā; it is a part of tathatā, and stands in a relationship with tathatā of neither being the same nor different.