Q: What is ultimate Buddhahood in the Perfect Teaching?

A: The self-wrought reward body of enjoyment of the Tathāgata Vairocana.

Q: How is this known?

A: In the Mo-ho chih-kuan [Chih-I’s The Great Calming and Contemplation] it says, “If one contemplates Twelvefold Conditioned Co-arising and culminates the reality of the Middle Path, this refers to the Buddha Vairocana of the Perfect Teaching. When he is seated on the seat of enlightenment, it becomes the seat of emptiness.” The Saddharma-puṇḍarīka-sūtra Upadeśa says, “Secondly, manifesting the wisdom of the Buddha [as reward body] and completing the practices of the Ten Stages, one attains the enlightenment of eternal Nirvāṇa, because, as the Lotus Sutra says, ‘Good sons, I have actually already attained Buddhahood immeasurable and unlimited hundreds and thousands and millions and billions of aeons ago.’ ” The Sutra of Meditation of the Bodhisattva Universal Virtue [Pu hsien kuan Ching] says, “The Buddha Śākyamuni is called ‘Vairocana Who Pervades All Places.’ This Buddha’s abode is called ‘Eternal Tranquil Light.’ It is a place that embodies the perfection of permanence; a place where the perfection of the selfhood is established; a place where the marks of Being are extinguished by the perfection of purity; a place where the marks of body and mind do not abide due to the perfection of pleasure.”