摩訶止觀 8.63

8.63

若偃臥毘耶，託疾興教，因以身疾，訓示凡俗，斥小呵大，乃共文殊，廣明因疾，三種調伏；廣明果疾，四種慰喻。又如來寄滅談常，因病說力，皆是權巧入病法門，引諸病惱。如此權病非今所觀。

As when [Vimalakīrti] reclined in Vaiśālī, using sickness as a pretext to initiate teachings, taking the physical illness of his body to instruct ordinary people, reproving the small and praising the great, and together with Mañjuśrī extensively elucidating the three kinds of subduing regarding causal sickness, and extensively elucidating the four kinds of consolation regarding fruition sickness. Furthermore, the Tathāgata's lodging in extinction to speak of permanence, and speaking of strength on the occasion of sickness, were all skillful means of entering the Dharma-gate of sickness to draw in all sickness and afflictions. Such provisional sickness is not what is contemplated at present.