法華經義記 3.25

3.25

問者言：「如來有身口二密，終日在坐不覩真容，雖復在中自不聞說法，何假從座而起拂席而去？」解釋者言：「此品中是時眾所應，亦可是實持是佛神力，將欲褒貶時眾，為令住者生欽重之心、起願樂之意，貶去者無聞法之緣，是故拂席而去也。」

The questioner asks: “The Tathāgata possesses the two secrets of body and speech. Even if one were to sit the entire day without seeing his true form, or though being within [the assembly] one naturally did not hear the preaching of the Dharma, why must one rise from one's seat, shake out one's robes, and leave?” The commentator explains: “In this chapter, it corresponded to the assembly at the time; or it may truly be sustained by the Buddha's supernatural power, intending to appraise the assembly of that time, in order to make those who remained give rise to reverence and produce the intention of wishing and delighting [in the Dharma], while disparaging those who departed as lacking the conditions to hear the Dharma; therefore they shook out their robes and left.”