When the Church comes together in the liturgical assembly to celebrate the Mass, or any other sacrament, her members do not gather simply as a crowd, as an amorphous, undifferentiated group of people. They gather in a variety of ministries and roles. If we are to understand the significance of these ministries and roles, we must begin with Baptism, for only one who through Baptism has been given a share in the priesthood of Christ is capable of participating in the public worship which is the liturgy of the Church. 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.
In addition to the ordained ministries there are roles in the liturgy which are exercised by lay people who place their time and talent at the service of the liturgical assembly as acolytes (altar servers), lectors, extraordinary ministers of Holy Communion, cantors, choir members, instrumentalists, leaders of song and ushers. Others contribute their time and talent to planning and organizing the liturgy, to keeping the church and the vestments, vessels and appointments clean and well-ordered or to providing decorations that reflect the spirit of the liturgical feast or season.
Those engaged in liturgical roles need to be well-prepared for those roles and to know how to carry them out with reverence, dignity and understanding. Obtaining the proper preparation requires a further gift of time on the part of the person being prepared as well as on the part of those in the parish responsible for the training of liturgical ministers. Finally, the practical task of assigning individuals to particular Masses and organizing the distribution of roles is another indispensable element in the fabric of well-ordered liturgical ministry in a parish.
But before individuals can be prepared for liturgical roles, there must first be individuals who are willing to assume those roles. All the baptized need to understand that part of their duty regarding liturgy is to accept some responsibility for the liturgy, to place themselves and their God-given talents at the service of the liturgical community whenever possible. If liturgy is a duty as well as a right, then part of that duty for those able to undertake these tasks is the responsibility to assume such key roles as those of lector, server or acolyte, extraordinary ministers of Holy Communion, usher, choir member, etc. . 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.