大乘起信論裂網疏 6.32

6.32

此文雖略，已含二十五前方便。住寂靜處，即是阿蘭若處，即攝具五緣也。結跏趺坐，必調五事。端身正意，即訶五欲、棄五蓋、行五法也。具加大、小《止觀》，須者尋之。

Although this text is brief, it already contains the twenty-five preliminary expedients. 'Staying in a quiet place' refers to an araṇya, which subsumes possessing the five conditions. 'Sitting cross-legged' necessarily involves regulating the five matters. 'Straightening the body and rectifying the mind' means scolding the five desires, discarding the five hindrances, and practicing the five dharmas. These are detailed in the Great and Small Calming and Contemplation; those who need them may look there.