瑜伽師地論略纂 7.117

7.117

無常、苦等四想中有三：初明四種所作、次明四種所治、後明四種能治之法。此下餘八所治及能治法，即出家後，設生喜樂，有懶惰懈怠等為四；遠離閑居，於止觀品闇昧心等為四。故於出家中，於四種所依事，起四種障，為除此故，修無常、苦等四想。

Within the four perceptions of impermanence, suffering, and so forth, there are three [parts]: first, clarifying the four kinds of tasks; next, clarifying the four kinds of things to be cured; and last, clarifying the four kinds of dharmas capable of curing them. Below this, the remaining eight things to be cured and dharmas capable of curing them are: after leaving the household life, even if one gives rise to joy and pleasure, there are four [defects], such as laziness and indolence; and in secluded dwelling, there are four [defects], such as a mind clouded regarding the division of śamatha and vipaśyanā. Therefore, within the household-renouncing state, with respect to the four kinds of foundational matters, four kinds of obstacles arise; to eliminate these, one cultivates the four perceptions of impermanence, suffering, and so forth.