四分律刪補隨機羯磨 1.47

1.47

（四明水界，如《五分律》，船上眾中有力人，以水若砂，四面擲所及處。此之六相，皆謂身面所向方隅限齊之內集僧，無人方可應法。）

(Fourth, explaining the water boundary: according to the Mahīśāsaka-vinaya, a strong person among the assembly on the boat throws water or sand in all four directions as far as it can reach. These six marks all mean assembling the saṃgha within the limits of the direction faced by body and face; only when no [eligible] person is absent does it conform to the Dharma.)