大方廣佛華嚴經隨疏演義鈔 62.86

62.86

疏「然始入佛法」下，第三通妨。難云：佛法大海，初信能入。何以至此方立信耶？通意可知。「今由前三科」者，即三四也。故《瑜伽》云「由如是增上心學、增上慧學所有瑜伽故，於大師弟子所證深生勝解，深生勝解已深生淨信。此清淨信增上義故，說名信根。」復應問言：信由三科，信不可拔。餘四由何復不可拔？答：餘四前修，至此成根。於理何失？

Regarding the commentary's "However, upon first entering the Buddha-Dharma" onward: (3) resolving an objection. The objection says: "The great ocean of the Buddha-Dharma is entered initially through faith; why is faith only established at this point?" The intention of resolving this is understandable. "Now, due to the previous three categories": that is, the three sets of four. Thus the Yogācārabhūmi states: "By means of the yoga associated with higher mental training and higher wisdom training in this manner, toward what the Master and disciples have realized, one generates deep resolute conviction; having generated deep resolute conviction, one generates deep, pure faith. Because of the predominant sense of this pure faith, it is called the faculty of faith." Again, one might ask: "Faith is due to the three categories, so faith is unshakable. By what are the other four also unshakable?" The reply: "The other four were cultivated earlier and become faculties at this point. What flaw is there in this principle?"