俱舍論頌疏論本 18.25

18.25

通三洲八等者，唯破羯磨通在三洲，有聖法故。極少八人，多亦無限，謂一界中僧分二部，別作羯磨，故須八人。過此無遮，故言八等。

"Extends to three continents, by eight or more": splitting only [the Saṅgha of] monastic acts (karman) extends across three continents, because the noble Dharma exists [there]. At the minimum there are eight persons, and more is also without limit; that is, within a single boundary (sīmā) the Saṅgha is divided into two factions performing monastic acts separately, and therefore eight persons are required. There is no prohibition against exceeding this; hence it says "eight or more."