ARTICLE
from the
Encyclopædia Britannica
priesthood, the office of a priest, a ritual expert learned in a special knowledge of the technique of worship and accepted as a religious and spiritual leader.
Throughout the long and varied history of religion, the priesthood has been the official institution that has mediated and maintained a state of equilibrium between the sacred and the profane aspects of human society and that has exercised a stabilizing influence on social structures and on cultic organizations. The term priest is derived etymologically from the Greek word presbyteros (“elder”), of which it is a contraction, and it is equated with the Latin word sacerdos (the Roman officiant at the sacrifices and sacred rites).