涅槃經遊意 1.202

1.202

又，明三德為開如來三密，故迦葉問願，佛開微密，廣為眾生說也。如此三密並《四相品》是也。亦是對凡夫三業，凡夫三業不密故。

Furthermore, it clarifies the three virtues in order to reveal the Tathāgata's three secrets; hence Kāśyapa made his request, wishing the Buddha to disclose the subtle and secret, explaining them extensively for sentient beings. These three secrets are all found in the 'Four Characteristics Chapter'. They also correspond to the three karmas of ordinary persons, because the three karmas of ordinary persons are not secret.