Q: The meaning of the One Vehicle is established on the basis of what Sutra passages?

A: The Lotus Sutra says, “All Buddhas, the World Honored
Ones, appear in this world for one great deed as cause and condition.”

Q: What is the meaning of “one great deed as cause and condition”?

A: “One” refers to the one true reality that there are not three, five, seven, or nine vehicles. Therefore it is “one.” It is called “great” because its nature is vast and expansive. It is called “deed” because it is the activity of all Buddhas who appear in this world. It is called “cause” because sentient beings who have the capability thus approach the Buddha. It is called “condition” because the Buddha responds in accordance with their capabilities.

Q: Although you have quoted this text, the meaning is still not clear. Are there other passages?

A: There are truly many passages. The Lotus Sutra says, “The words of all Buddhas and Tathāgatas are not vain delusions. There is no other vehicle but the one Buddha-vehicle.” It also says, “In the Buddha-lands in the ten directions there is only one Buddha dharma, not two and not three.” It also says, “The appearance of all Buddhas in this world is only one true deed.” It also says, “All the World Honored Ones expound the Path of the One Vehicle.” It also says, “The words of all the Buddhas are not different. There is only one and not two vehicles.” It also says, “It is widely said to the great multitude that all Bodhisattvas and Śrāvaka disciples are taught and transformed only with the way of the One Vehicle.”

Also, the chapter on “Expedient Means” [in the Lotus Sutra] contains sections on five kinds of Buddhas. The first section on “All Buddhas” says, “All Buddhas preach the Dharma in accordance with what is appropriate.” This [illustrates that] the three tentative [teachings: Tripiṭaka, Shared, and Distinct] are the exposition of expedient means. The Sutra says, “This Dharma cannot be understood through conceptualization or discrimination.” This [illustrates] the One True [Perfect Teaching], which manifests true reality. Next, the section on the Buddhas of the past says, “All Buddhas utilize innumerable and incalculable expedient means and various stories, parables, and words to expound all Dharmas for the sake of all sentient beings.” This clarifies the exposition of the tentative. The Sutra says, “These Dharmas are all those of the One Buddha-vehicle.” This clarifies the manifestation of the real. Next, the section on future Buddhas says, “Śāriputra, all future Buddhas should, upon appearing in this world, utilize innumerable and incalculable expedient means and various stories, parables, and words to expound all Dharmas for the sake of all sentient beings.” This clarifies the exposition of the tentative. The Sutra says, “All of these Dharmas correspond to the One Buddha-vehicle. Therefore all sentient beings hear the Dharma from the Buddha and everyone ultimately attains universal wisdom.” This clarifies the manifestation of the real. Next, the section on present Buddhas says, “Śāriputra, at the present time, in the immeasurable hundred thousand million billion Buddha-lands in the ten directions, in the many places where all Buddhas, World Honored Ones, benefit and pacify sentient beings, all of these Buddhas also utilize innumerable and incalculable expedient means and various stories, parables, and words to expound all Dharmas for the sake of sentient beings.” This clarifies the exposition of the tentative. The Sutra says, “All of these Dharmas correspond to the One Buddha-vehicle. Therefore all sentient beings hear the Dharma from the Buddha and everyone ultimately attains universal wisdom.” This clarifies the manifestation of the real. Next, in the section on the Buddha Śākyamuni it says, “Śāriputra, I also now do the same. Knowing that all sentient beings have various desires and profound attachments, I therefore utilize various stories, parables, words, and the power of expedient means in order to preach the Dharma, in accordance with their inherent natures.” This clarifies the exposition of the tentative. The Sutra says, “Śāriputra, in this way all attain the One Buddha vehicle and universal wisdom.” This clarifies the manifestation of the real.