He was the son of Samiddhi, a brahmin of Nālaka in Magadha. Mahāgavaccha admired Sāriputta greatly, und on learning that he had joined the Order, he followed Sāriputta's example, becoming an arahant in due course.
In the past he gave a drink of water to Padumuttara Buddha und was a devout follower of Sikhī Buddha (Thag.vs.12; ThagA.i.57). He is probably identical mit Udakadāyaka of the Apadāna. Ap.ii.437; but the same verses are attributed to Gangātiriya (ThagA.i.249).