藥師經疏 1.121

1.121

經。時婆伽婆至歡喜奉行　自下第三明依教奉行分聞佛所說歡喜奉行者。依伽耶山頂經論云。天親菩薩明三種清淨。所以歡喜。一說者淨明如來是一切智人。普為眾生盡說頓說無有藏法之垢故說者清淨。二所說法淨明所說經教與理相應隨順善導句義美妙故所說清淨。三受法者淨明聽法之時一心正信不相是非聞即受行故。受者清淨具三清淨所以歡喜。

Sūtra: 'At that time, the Bhagavat […] rejoiced and faithfully practiced it.' From here down is the third [division], which clarifies the section on faithfully practicing according to the teaching. Regarding 'hearing what the Buddha said, they rejoiced and faithfully practiced it': according to the *Gayaśīrṣa-sūtra-śāstra*, Bodhisattva Vasubandhu explains three kinds of purity, which is why they rejoiced. First is the purity of the speaker: this clarifies that the Tathāgata is omniscient, expounding completely and all at once for the sake of all sentient beings, free from the defilement of concealing the Dharma; hence the speaker is pure. Second is the purity of the expounded Dharma: this clarifies that the scriptural teaching expounded corresponds to principle, complies with and skillfully guides, and its phrases and meanings are exquisite; hence the expounded [Dharma] is pure. Third is the purity of the receiver of the Dharma: this clarifies that when listening to the Dharma, with one mind and correct faith they do not dispute right and wrong, and upon hearing it they immediately accept and practice it; hence the receiver is pure. Having these three purities, they therefore rejoiced.