法華義疏 8.47

8.47

「一時等澍其澤普洽」者，第四、明雨譬。法施無前後，故云一時。又云有感同聞。又如一時為說不偏故云等澍，遍益無邊義同普洽。

As for "pouring down equally at one time, its moisture universally enriching," this is the fourth [part], explaining the parable of rain. The gift of Dharma has no before and after, hence it says "at one time." It also means that those who have the evocation hear it together. Moreover, just as he preaches at one time without partiality, it says "pouring down equally"; benefiting boundlessly and everywhere has the same meaning as "universally enriching."