大般涅槃經義記 4.176

4.176

上來廣明經法為醫，下二復次以人為醫，經由人傳是以論之。前一復次通說諸佛菩薩為醫，後一偏說佛為良醫。化凡之醫義通上下，故前通說諸佛菩薩以為良醫；教聖之醫局唯在上，故後偏說如來為醫。前中先喻，「良醫」喻於諸佛菩薩，「善知八種」喻備化德，「悉能療」等明其化能，「唯不能」下簡去闡提。下合可知。

The preceding has extensively explained the Dharma of the sūtra as the physician; the next two passages take persons as the physician. It is discussed because the sūtra is transmitted through persons. The first passage generally speaks of all buddhas and bodhisattvas as physicians; the second passage specifically speaks of the Buddha as the skilled physician. The physician who transforms ordinary beings applies generally to both higher and lower, hence the former generally speaks of all buddhas and bodhisattvas as skilled physicians; the physician who teaches aryas is restricted solely to the higher, hence the latter specifically speaks of the Tathāgata as the physician. Within the former, it first gives the simile: "skilled physician" is a simile for all buddhas and bodhisattvas; "well versed in the eight kinds" is a simile for being fully equipped with the virtue of transforming; "all of which he can treat" and so forth explains their transformative ability; from "only unable to" below, it excludes icchantikas. The application below can be understood.