A disciple of Ānanda who played an important part in the Council of Vaiśālī. It was Yasa who discovered and brought to light the ten illicit practices (Pāli, dasavatthu) of the Vajjian monks.such as handling gold and silver (meaning accepting donations of money). Largely due to his efforts, a committee of eight venerable monks was formed (on which he served) to investigate the disputed practices. After due consideration all ten were declared to be illegal and the Vinaya was recited by 700 monks. This recital is referred to as the ‘recital of the Elder Yasa’ (yasathera-saṇgīti) in recognition of the role he played in the proceedings.