成唯識論述記 6.64

6.64

述曰：經中所說，說欲所起一切事業，由欲為彼本，通三性法，皆有勤故。由此文知，入法初首，由善法欲，能發精進。由精進故，助成於欲一切善事；此即說，欲為諸善法本。如說信為法本，但是善因；欲為法本，理應如是。《對法》十五謂：一切法欲為根本，乃至出離為後邊等。故《對法》、《顯揚》皆說：勤依為業，欲通緣三世，欲作意觀故，非唯未來。以前三師，一一三世辨對可知。

The Commentary states: What is stated in the sūtra refers to all undertakings initiated by desire, because desire is their root; since it applies to phenomena of the three natures, diligence is always present. From this passage we know that at the very beginning of entering the Dharma, it is through the desire for wholesome phenomena that one is able to produce energetic striving. Through energetic striving, one assists in bringing to completion all wholesome undertakings of desire; this is what is meant by saying that desire is the root of all wholesome phenomena. Just as it is said that faith is the root of the Dharma, being solely a wholesome cause, so too, by principle, it should be with desire as the root of phenomena. The fifteenth fascicle of the Abhidharma-samuccaya states that all phenomena have desire as their root, up to liberation as their culmination, and so forth. Therefore, both the Abhidharma-samuccaya and the Prakaraṇāryavācā state: 'Its function is to serve as the basis for diligence.' Desire applies across cognition of the three times, because it observes with the intention to direct attention; it does not pertain solely to the future. With respect to the preceding three masters, it can be understood by examining how each addresses the three times.