We have no better information about the priests of the West than we have on the political and social position of the priests of Eastern Iran. They are not called Athravas but Magush. This name is first found in the inscription which Darius caused to be cut on the rock-wall of Behistun; afterwards it was consistently used by Western writers, from Herodotus to Agathias, for the priests of Iran. The Avesta has the words _magha_ and _maghavan_, i.e. the powerful, the great,[319] but does not use it of the priests, which are always called Athravas. If the last title is taken from the fire-worship, the first allows us to see the importance of the priests. He who can use incantations to the gods and spirits--can summon or remove them--is the mighty one, the powerful. If in this name we have evidence of the respect with which the laity of Western Iran looked up to the priests, the difference between the names in the East and West shows that there were priestly races among the Medes and Persians before the religion of Zarathrustra reached them. Had not such existed before the reform, and had they not possessed a definite name in the West--had priestly families become known there for the first time at the rise of the reform--they would never have had any other name than that of Athravas. Even without this positive proof we might assume that from all antiquity there had been priests among the Medes and Persians who understood how to invoke the gods of light in the old Arian faith--Mithra and Verethraghna, Vayu and Tistrya--and tend the fire which destroyed demons. When the new doctrine reached from the East to Ragha and then to Media (p. 96), the old races who passed over to the new faith united with the families the members of which were the prophets of the new doctrine. The teachers of the Medes in old times, which Pliny called successors of Zarathrustra, might have stood at the head of this transformation of the ancient priestly families, of the creation of the Median priesthood on the basis of the new religion (p. 92). However this may have been, the priestly families among the Medes were so numerous, their connection and union so close and firmly fixed, that they could be counted as a sixth tribe beside the other five Median tribes.