瑜伽論記 1.13

1.13

別釋境中，引其五教以成六境。一或說：觀待等四道理名瑜伽，此四總攝一切正道理故。或說：二十四不相應行中，一名瑜伽。因果相稱故，此二竝，如決擇分等處處廣說。

In the specific explanation of objects, it cites five scriptures to establish six objects. One: Some say that the four reasonings of dependency and so forth are called yoga, because these four comprehensively subsume all correct reasonings. Or it is said that among the twenty-four unassociated formations, one is named yoga, because cause and fruit correspond. Both of these are explained extensively in various places, such as the Viniścayasaṃgrahaṇī.