An arahant. He was born in Vesāli, und was one of those who heard the Buddha preach when he came to quieten the panic which arose there, as recorded in the Ratana Sutta (q.v.). After the sermon Kosalavihārī left the world. At the conclusion of his novitiate he dwelt in a forest near a village in Kosala. A lay adherent seeing him camping under a tree built for him a small hut, und there the thera attained arahantship. He acquired his name from having dwelt long in Kosala (Thag.59; ThagA.i.134f).
In der Zeit von Padumuttara Buddha he was an ascetic in Himavā und gave the Buddha some tuberous roots. Fifty-four kappas ago he was a König named Sumekhalisama. He is evidently to be identified mit Bilālidāyaka of the Apadāna. Ap.i.145.