摩訶止觀 5.21

5.21

病患是法界者，《淨名》云：「今我病者非真非有；眾生病亦非真非有。」以此自調，亦度眾生。方丈託疾，雙林病行，即其義也。

Illness being the dharmadhātu: the Vimalakīrtinirdeśa says, "My present illness is neither real nor existent; sentient beings' illnesses are also neither real nor existent." Through this one tunes oneself, and also delivers sentient beings. Feigning illness in the ten-foot-square room, and the practice of illness in the Twin Groves, convey this very meaning.