A public service, duty, or work. In Scripture it refers to the religious duties to be performed by priests and levites in the Temple, especially those related to the Sacrifice; in Christian use among the Eastern Churches it means the Eucharistic Sacrifice.
In present day usage liturgy is the official public worship of the Church and is thus distinguished from private devotion. It is the special title of the Eucharist, and the administration of the sacraments with the annexed use of the sacramentals.
From a theological viewpoint, the liturgy is the exercise now on earth of Christ's priestly office, as distinct from his role as teacher and ruler of his people. Christ performs this priestly office as Head of his Mystical Body, so that Head and members together offer the sacred liturgy. Its function, therefore, is twofold: to give honor and praise to God, which is worship, and to obtain blessings for the human race, which is sanctification. (Etym. Latin liturgia; from Greek leitos, of the people + ergon, work: leitourgia, public duty, public worship.)