淨名經集解關中疏 2.23

2.23

譬如長者唯有一子其子得病父母亦病。若子病愈父母亦愈　此二喻也。

"'For example, just as an elder has only an only son, and if that son falls ill, the parents are also ill; if the son's illness is cured, the parents are also cured'"—this is the second, the metaphor.