Based upon Roman Missal Formational Materials provided by the Secretariat for the Liturgy of the United States Conference of Catholic Bishops, " www.usccb.org, 2010
When the Church comes together in the liturgical assembly to celebrate the Mass, we gather in a variety of ministries and roles. Through Baptism we have been given a share in the priesthood of Christ. In fact, the Constitution on the Sacred Liturgy of the Second Vatican Council tells us that participation in the liturgy is the right and duty of all the baptized. Whether one brings up the gifts at the Presentation, reads the Word of God, assists with the distribution of Communion and brings the Eucharist to those unable to be present at Mass, serves at the altar, provides music that augments the joy, solemnity and festivity of the celebration or serves the assembled community as an usher, he or she is contributing to the worship of the community and fulfilling the responsibility that comes with Baptism.
The liturgy, then, is about the action of God's own people, each with different offices and roles, each office and role, from that of bishop and priest to that of usher and sacristan, one of service, not of privilege, a mirror of Christ who washed the feet of his disciples and instructed his followers to imitate his example of service.