瑜伽論記 13.145

13.145

義曰：若有情身及外別受用果，須業盡時果盡，有業時緣外器別果，其外共器果未必要須業，一有方便緣，以一切時任運緣彼為境界故。

The reasoning is: With respect to sentient beings' bodies and external distinct fruition of enjoyment, the fruition must be exhausted when karma is exhausted; when there is karma, one takes the distinct fruition of the external vessel as an object. The common vessel fruition outside does not necessarily require karma once there are expedient conditions, because it spontaneously takes that as an object at all times.