釋氏要覽 2.41

2.41

This is an etiquette of Tianzhu. This rite has lapsed since the Cao-Wei period down to the present. The Vinaya says that baring the right shoulder means baring the flesh. The Vinaya says: For all offerings, one bares one shoulder, showing readiness to perform manual work. It is also as Zhongni (Confucius) said: Gathering up the right sleeve facilitates doing work. (Saying 'all offerings' refers to seeing the Buddha, paying homage to the Buddha, paying homage to the two masters, and so forth.) If entering villages or lay dwellings, one covers both shoulders with the kāṣāya.