Priest, a person set apart for the performance of religious offices and ceremonies, and in particular for the performance of sacrifice. History shows the priestly office to be nearly coextensive with religion itself, and there is hardly a barbarous tribe without some sort of priests. There is but little information concerning the exercise of priestly functions before the time of Moses. We read in the Scriptures of Cain and Abel offering their own sacrifices, and of the exercise of the priestly office by the heads of families, as Abraham, or Job. The term priest occurs but once in the book of Genesis, when Melchizedek is called a priest of the Most High. The Mosaic law established a special priesthood consisting of three orders, the high priests, the priests, and the Levites, all of them from the tribe of Levi. The priesthood was hereditary in the family of Aaron; and the first born of the oldest branch of that family, if he had no legal blemish, was the high priest. This was observed till the Jews fell under the dominion of the Syrian Greeks; then and afterward under the Romans the high priesthood was sometimes put up to sale, and became a temporary office.

In the time of David the inferior priests were divided into 24 companies, each company serving in rotation for a week. - The early history of the priesthood of the several pagan religions is involved in obscurity, though elucidated in many important details by modern criticism. With most of the uncivilized tribes the priest had a very limited sphere of action; he generally appears as a sorcerer, who derives by communication with a spirit world the command of magic powers for the relief of the distressed and suffering. With some tribes this power was the only attribute of the priesthood; with others they had the office of divining, and of offering sacrifices. In the Society islands and New Zealand the priesthood formed a hereditary corporation; but nowhere among pagan tribes have they been so powerful as in Mexico, where they are said to have numbered 4,000,000 on the arrival of the Spaniards. - The idea of priesthood was much more fully developed by Brahmanisin. The Brahmans have assigned to them the primacy of honor among the castes of India, and it is easy to trace in the enormous prerogatives with which they are clothed the fundamental idea of a vicegerency of God upon earth.

Brahmans are also charged with preserving the soundness of doctrine, and with presiding over sacrifices and divine services. - The state church of China, which owes its organization "to Confucius, has no special priesthood, but the priestly functions are blended with those of the emperor and the state officers. The Buddhist priests, called lamas in Mongolia and Thibet, bonzes in Japan, rahans in Burmah, talapoins in Siam, and gunnis in Ceylon, are essentially spiritual guides. They are to be examples of a perfect life, consisting, according to Buddhist views, in overcoming matter, accumulating merits, and thus preparing for a higher second birth. They do not form a caste; they live in celibacy, and the chief of the central Asian Buddhists, the dalai lama, is regarded as the incarnation of Buddha himself. (See Lama-ism.) The magi of the Persians were the conductors of religious services and the teachers of the people. In Egypt the priests likewise formed one of the supreme castes, endowed with many privileges, and exempt from taxation. They were divided into several classes, and constituted a complete hierarchy, on a democratic basis, with a chief priest at their head.

More than any other pagan priesthood, they gained their preeminence and secured the continuance of their prerogatives by their literary superiority. The ancient religion of the Greeks had no general priesthood, but only priests of the several deities, who slaughtered the victims, and often secured a powerful influence as the interpreters of the will of the deity. Finally the priestly office among them fell into utter insignificance. The Roman priesthood was to a larger extent than that of any other great nation of antiquity charged with the office of divining. It was a well organized and largely privileged state institution, which retained its social position and political influence when the belief in its faculty of divining had entirely ceased among the educated classes, and when Cicero, as he says, wondered how two augurs could meet without laughing at each other. - In the Christian system the gospel represents Christ as the one priest, who, for the redemption of the world, offered the one sacrifice, that of the cross. So far all who receive the record of the gospel as infallibly true agree; but there is a fundamental difference of opinion on the question, whether this sole priesthood of Christ is incompatible with the existence of a proper priestly office in the church.

The Roman Catholic church, and those eastern churches (Greek, Armenian, Nestorian, Jacobite, Coptic, Abyssinian) which regard ordination as a sacrament, maintain that the sacrifice of the cross was to be continued and kept perpetually present in the church through appointed representatives and vicegerents of Christ, who for that purpose continue and partake in the priestly character of Christ and his mediatorial office between God and man. (See Ordination.) The other Christian denominations deny that there is in the Christian church any other real priest than Christ, since there is no one after Christ who has the power of offering sacrifices for the people. But they believe in a spiritual priesthood of all Christians, which they derive from their union with Christ, the sole high priest. They therefore do not regard the clergy as an order specifically distinct from the laity, but only as the body of teachers and servants of the church, who, being divinely called and properly appointed, possess certain ecclesiastical rights and undertake certain duties, which they derive partly from divine, partly from human law. (See Clergy.) The Protestant Episcopal churches of England, Scotland, Ireland, and America have retained the word priest, to denote the second order of their hierarchy.