瑜伽論記 22.72

22.72

第三約四門分別苾芻中，言具足別解脫律儀眾同分，是其自性者，於別解脫上假立眾同分，眾同分是比丘自性，以薩婆多和合為僧自性。言於其形色至名為苾芻者，此訓詞也，剃除鬚髮，著袈裟等故言其形色等。言門差別者，謂剎帝利等，差別故者，明苾芻中有四姓出家不同也。

In the third, distinguishing the bhikṣu according to the four divisions: the statement "being endowed with the genus-counterpart of the prātimokṣa discipline is its essential nature" nominally posits the genus-counterpart upon the prātimokṣa, the genus-counterpart being the essential nature of a bhikṣu, taking the Sarvāstivādin harmony as the essential nature of the saṅgha. The statement "regarding its bodily form and appearance" up to "is called a bhikṣu": this is the gloss on the words; shaving the hair and beard, wearing the kāṣāya, and so forth are why it says "its bodily form and appearance" and so forth. The statement "the differentiation of divisions refers to kṣatriyas and so forth, due to their differences" clarifies that among bhikṣus there are differences in renunciation from the four castes.