摩訶止觀 8.144

8.144

報因、報果者，此就異世。前習因、習果皆名報因，此因牽來果，故以報目之，名為「報因」；後受五道身，即是「報果」也。

As for retributive cause and retributive fruit, this is with reference to different lifetimes. The preceding habitual cause and habitual fruit are both called retributive cause; this cause drags forth a future fruit, so it is designated by retribution and called "retributive cause." Subsequently receiving a body in the five paths is precisely the "retributive fruit."