Pāvā was evidently a centre of Buddhist activity even during the lifetime of the Buddha, and mention is made of Pāveyyaka monks in the Vinaya (e.g., Vin.i.253). During the time of the Vajjiputtakā heresy, it was the Pāveyyakā monks who upheld the true doctrine, their leaders being Revata, Sambhūta Sānavāsi, Yasa Kākandakaputta, and Sumana (Vin.ii.301 ﬀ; Mhv.iv.17 ﬀ). In this connection the Pāveyyakā are also described as “Pacchimikā” in opposition to the Vajjiputtakā who are called “Pācīnakā.”
It is explained (e.g., MT.166) that the Pāveyyakā were called “Pacchimikā” because they lived to the west. West of Kosala, according to Buddhaghosa, on Mahā Vagga (vii.1).