As Liturgical Ministers, parishioners of all ages have the opportunity to actively participate and serve in Mass.
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CONSTITUTION ON THE SACRED LITURGY (SACROSANCTUM CONCILIUM)
14. Mother Church earnestly desires that all the faithful should be led to that fully conscious, and active participation in liturgical celebrations which is demanded by the very nature of the liturgy. Such participation by the Christian people as "a chosen race, a royal priesthood, a holy nation, a redeemed people" (1 Pet. 2:9; cf. 2:4-5), is their right and duty by reason of their baptism.
28. In liturgical celebrations each person, minister or layman, who has an office to perform, should do all of, but only, those parts which pertain to his office by the nature of the rite and the principles of liturgy.
29. Servers, lectors commentators, and members of the choir also exercise a genuine liturgical function. They ought, therefore, to discharge their office with the sincere piety and decorum demanded by so exalted a ministry and rightly expected of them by God's people.
Consequently they must all be deeply imbued with the spirit of the liturgy, each in his own measure, and they must be trained to perform their functions in a correct and orderly manner.