妙法蓮華經玄義 5.114

5.114

四、明圓教三法者，以真性軌為乘體。不偽名真，不改名性，即正因常住，諸佛所師，謂此法也。一切眾生亦悉一乘，眾生即涅槃相，不可復滅；涅槃即生死，無滅不生。故《大品》云：「是乘不動、不出。」即此乘也。

Fourth, in clarifying the three dharmas of the perfect teaching, the track of the real nature is taken as the substance of the vehicle. Unfalsified is named 'real', unaltering is named 'nature'; that is, the proper cause that is constantly abiding, what all buddhas take as master—this is that dharma. All sentient beings are also entirely the single vehicle; sentient beings are themselves the mark of nirvāṇa, which cannot be extinguished again; nirvāṇa is itself saṃsāra, without extinction and unarisen. Thus the Pañcaviṃśati-sāhasrikā-prajñāpāramitā-sūtra says: 'This vehicle does not stir, does not go forth.' It is precisely this vehicle.