釋氏要覽 3.312

3.312

Today, on the day monks in western Zhejiang conclude the summer retreat, they bind grass into bundles with coloured silk to give to the dānapatis, calling it "grass for ending the summer retreat." Examining this grass now, it is named "auspicious grass" (kuśa) because it serves as the seat for the fivefold Dharma-body. The Mūlasarvāstivāda-ekaśatakarman states: "The bhikṣu who has received pravāraṇā should distribute these bundles to serve as seats for the Saṃgha; all the bhikṣus then sit upon the grass." ("Following wishes" (隨意) means pravāraṇā (自恣). "Saṃgha" means the assembly. They spread the grass on the ground to sit on it.)