瑜伽論記 24.208

24.208

言一、據相應俱行義者，即與七覺同時相應，謂無常等想俱行修乃至死想俱行修，此據已得聖人後得智中作此觀行故，與七覺相應；二、據無間俱行義，謂不淨等想乃至觀空想者，此據方便道中作不淨觀，乃至觀唯尸骸空心識，即與七覺前後相入名據無間義慈等亦爾者，此汎爾例非在二十一想數中有慈等觀。

Regarding 'first, based on the meaning of co-occurring in association,' this means being simultaneously associated with the seven factors of awakening, namely, cultivation co-occurring with the notion of impermanence and so forth up to cultivation co-occurring with the notion of death; this is stated based on noble beings who have already attained it performing this contemplative practice in their subsequent wisdom, hence it is associated with the seven factors of awakening. 'Second, based on the meaning of co-occurring immediately without interval,' this refers to the notion of impurity and so forth up to contemplating the notion of emptiness; this is stated based on performing the contemplation of impurity in the path of preparation, up to contemplating only a corpse being empty of mental consciousness, which then enters into and alternates before and after with the seven factors of awakening, called 'based on the meaning of uninterruptedness.' 'Benevolence and so forth are also like this' is just a general analogy; contemplations such as benevolence are not included in the count of the twenty-one notions.