大毘盧遮那成佛經疏 6.157

6.157

Where the beginning of the second fascicle of the root sūtra states, "At that time the Bhagavat Vairocana assembled together with all buddhas, and each proclaimed the samādhi paths of all śrāvakas, pratyekabuddhas, and bodhisattvas," [it means that] the Tathāgata, having already expounded the ultimate mudrā of the threefold emptiness samādhi, then expounded the differentiated mudrās within the samādhi paths in order that those advancing through the universal gateway should encounter no impediments. The various diverse forms displayed in the triple maṇḍala are all single Dharma-gate bodies of the Tathāgata, and therefore are all named "buddha." Each of these buddhas, in the Dharma gateway originally propagated by them, himself expounds that samādhi path: if manifesting the body of a worldly deva, he expounds that deva's samādhi path; if manifesting the body of a śrāvaka, he expounds the śrāvaka samādhi path; if manifesting the body of a pratyekabuddha, he expounds the pratyekabuddha samādhi path; if manifesting the body of a bodhisattva, he expounds the bodhisattva samādhi path; if manifesting the body of a vajradhara, he expounds the vajra samādhi path. One should know that the verses here are as countless as the dust particles of buddha fields, not something that could be fully recorded in worldly compilations of sūtra scrolls. However, when practitioners deeply enter the samādhi of the yoga realm, they will naturally hear them clearly, no different from when they were being spoken, which is why it is called "the day of the Buddha's adhiṣṭhāna."