大般涅槃經疏 19.14

19.14

「以病增故」下，第二明根緣感佛。病增譬斷善心重。諸家親屬者，三解：一云過去戒善感此人身，唯此善在，譬之親屬；二云闡提斷過現善盡，而當善方生，皆應作佛，名未生善以為親屬；三云不然，自有善感佛、自有惡感佛，闡提無善但以惡感，惡為親屬。即是遣使請醫形體缺短者，若以善為使，此善為惡所瘵，故云缺短。將若惡為使，此惡道理自是痤陋，善根微弱故言缺，信不具故故言短。私云：信等不具故云根不具足。頭蒙塵土者，五住所覆。著敝壞衣者，被無慚愧。載故壞車者，藉先世善感此人身殘缺善根。私云：冥機冥叩，故云語醫速疾。上車者，立望感應。

From 'Because the illness increases...' onward is the second [part], explaining that capacities and conditions stimulate the Buddha. The increase of illness illustrates the mind severing goodness growing heavier. Regarding the relatives of various families, there are three explanations: The first says that past morality and goodness stimulate this human body, and only this goodness remains, illustrated by relatives. The second says that the icchantika has severed past and present goodness completely, but future goodness is just about to arise, and all should become buddhas; the unborn goodness is called the relatives. The third says this is not so: some stimulate the Buddha with goodness, and some stimulate the Buddha with evil; the icchantika lacks goodness and stimulates solely through evil, so evil serves as relatives. That is to say, sending an emissary to invite a physician whose physical form is deficient and short: if goodness is taken as the emissary, this goodness is plagued by evil, hence it is said to be deficient and short. If evil is taken as the emissary, by the principle of this evil it is naturally dwarfed and ugly; the roots of goodness are faint and weak, hence it is called 'deficient', and because faith is incomplete, it is called 'short'. In my personal view: because faith and the others are incomplete, it is said that 'the faculties are incomplete'. Having the head covered in dust and dirt means being covered by the five entrenchments. Wearing tattered and ruined clothes means being enveloped in lack of shame and remorse. Riding in an old and broken carriage means relying on the past life's goodness that stimulated this human body with its damaged and deficient roots of goodness. In my personal view: dark resonance and dark knocking are why it says 'telling the physician to come swiftly'. Boarding the carriage means establishing the expectation of stimulus and response.