瑜伽論記 4.217

4.217

四因緣入等至中，因力者，謂前生當所入定以為因力，此順小教作此分別理論，大乘正取定種以為因力，亦可據曾隣近入靜慮時，熏發定種功能增長生今時定，是其因力。

In entering meditative attainments through four conditions, as for the "power of the cause": it refers to the meditative concentration to be entered in a future rebirth serving as the power of the cause; this follows the Hīnayāna teaching in making this distinction. According to the doctrinal theory of the Mahāyāna, the seeds of meditative concentration are properly taken as the power of the cause; it can also be based on having previously been in proximity to entering dhyāna, perfuming and cultivating the seeds of concentration so that their capacity increases to generate the concentration of the present moment—this is its causal power.