大般涅槃經集解 43.46

43.46

案僧亮曰：譬如來為闡提說法。如醫審知病者必死，不得不說法，一為病人、二為親族。諸佛亦爾，不得不說也。

Sengliang notes: This exemplifies the Tathāgata preaching the Dharma for icchantikas. Just as the physician clearly knows the patient will surely die, yet cannot but preach the Dharma—first for the patient, and second for the relatives—the Buddhas are also like this and cannot but speak.