大般涅槃經集解 52.10

52.10

案僧亮曰：道見由道，次第說道也。聞修定在死尸間，多怖畏，令修六念以除其畏也。僧宗曰：前三念是外念，次戒施是內行，後念天是未來果也。寶亮曰：第三聚也。自佛出世便有此六矣，〈梵行品〉已廣釋也。

Sengliang states: The view of the Path arises from the Path, so the Path is expounded in sequence. Hearing that cultivating concentration among corpses causes much fear, [the Buddha] instructs them to cultivate the six recollections to remove their fear. Sengzong states: The first three recollections are external recollections; next, precepts and giving are internal practices; the final recollection of devas is the future fruition. Baoliang states: This is the third group. Ever since the Buddha appeared in the world there have been these six; they were already extensively explained in the 'Chapter on Pure Practices'.