Younger brother of Devānampiyatissa.
He witnessed the miracles which attended the arrival of the Buddha's Relics in Ceylon, and, with one thousand others, entered the Order (Mhv.xvii.57f).
When Mahā Arittha recited the Vinaya at the Thupārāma and held the Sangīti at the suggestion of Mahinda, Mattābhaya, with five hundred others, was charged with the duty of learning the Vinaya from him. Sp.i.103.