“Upāli. An eminent Arhat disciple of the Buddha famed for his knowledge of monastic law and discipline (Vinaya). A member of the barber clan in the Buddha’s home town of *Kapilavastu, Upāli sought *ordination when the Buddha first returned to see his family after gaining enlightenment (*bodhi). As a *monk he devoted himself to the study of the monastic rules and held numerous discussions with the Buddha over problematic cases. These questions and answers are recorded in the *Parivāra section of the *Vinaya Piṭaka. In the *First Council held at *Rājagṛha, Upāli was called upon to recite the Vinaya, which, according to tradition (almost certainly erroneously), was fixed at that time.” (PDoB)
See Buddha’s Ten Great Disciples
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