俱舍論記 7.53

7.53

「論曰至有作用故」者，釋初句。相應、俱有於果法滅位興與果用，住、異雖亦同時，滅相義當在後，故偏言滅。由此二因滅位興用，令俱生、士用果有作用故、或令俱生果有作用故、趣所緣境及一果等。又《正理》云「如是二因，雖俱一時取果，與果，而今但約與果功能。」

Regarding 'The treatise says: … because they have function': this explains the first line. The associated and co-existent causes exercise their function of bestowing the result at the stage of cessation of the result dharma. Although abiding and alteration are also simultaneous, the characteristic of cessation is logically situated after them, hence it speaks specifically of cessation. Because these two causes exercise their function at the stage of cessation, they cause co-arising and virile results to have activity, or cause co-arising results to have activity, moving toward an objective field and a single result, and so forth. Furthermore, the Nyāyānusāra states: 'Although these two causes grasp the result and bestow the result at the same time, now it is only spoken with respect to the capacity to bestow the result.'