There is more than one criterion by which men may be set apart as priests. Sometimes they are those who in a mystic state of ecstasy are supposed to be inspired by the gods. During their trance such men are questioned as to the will of the divine. Sometimes they become renowned through their reputed performance of an occasional miracle. Again, as magical and religious ceremonies become more complicated, there is a deliberate training of an expert class to perform these essential acts. And, whatever be the source of the selection of the priestly class, the immense influence which their functions are regarded as having on the welfare of the tribe causes them to be particularly revered and often feared by the lay members of the tribe. In more civilized and spiritual religions, the priestly or professional ecclesiastical class is no longer regarded as possessed of magical powers by which it can coerce divinity. It is the official administrator of the ceremonies of religion, is especially trained, versed and certificated in doctrine, is empowered to receive confession, fix penance, and the like. It is still an intermediary between man and the divine, although itself not possessing any supernatural powers. Where ecclesiastical organization is highly developed and has become controlling in the life of a people, it may be one of the most powerful forces in social life. Such, for example, might be said of the Catholic Church during the Middle Ages: A life in the Church, for the Church, through the Church; a life which she blessed in mass at morning and sent to peaceful rest by the vesper hymn; a life which she supported by the constantly recurring stimulus of the sacraments, relieving it by confession, purifying it by penance, admonishing it by the presentation of visible objects for contemplation and worship--this was the life which they of the Middle Ages conceived as the rightful life of Man; it was the actual life of many, the ideal of all.[1] [Footnote 1: Bryce: _Holy Roman Empire_, p. 423.] Churches may also come to acquire political functions. The history of the Church is for many centuries the leading factor in the political history of Europe, nor is it only in Christendom that political institutions have been inextricably associated with religion.