大方廣圓覺修多羅了義經略疏 1.899

1.899

上僧祇等算此世界之數也，謂有百千萬億僧祇等數之河，一一河中一沙為一界，以顯世界如是多矣。然此中意者，直至盡虛空遍法界所有世界，不是算其數量，為欲引機造無邊境，故假增積多數爾。然淨穢等土皆佛統之，故云佛界。

The asaṃkhyeyas and so forth above calculate the number of these worlds; that is, there are hundreds of thousands of myriads of koṭis of asaṃkhyeyas of such rivers, and each sand grain in each river is a world, thereby showing that the worlds are so numerous. However, the intent here extends directly to all worlds to the exhaustion of empty space and pervading the dharmadhātu; it is not to calculate their quantitative measure, but because of the desire to lead faculties to create a boundless realm, it provisionally aggregates and multiplies large numbers, that is all. Moreover, pure and defiled lands alike are all governed by the Buddha, and therefore they are called "buddha-worlds."