 de Casparis observes, 'The most important detail is the name of the foundation, the Abhayagiri Vihara.Abhayagiri Vihara appears to have been a center for Mahāyāna and Vajrayāna teachings; as such, it was seen as heretical by more conservative Mahavihara monks.In the 7th century CE, Xuanzang also describes the concurrent existence of both monasteries in Sri Lanka, and refers to the monks of the Mahavihara as the "Hīnayāna Sthaviras" (Pali