The sacred liturgy, by its very nature, is the worship of the Heavenly Father by Christ united with all the members of the Church—his Mystical Body.
Mother Church earnestly desires that all the faithful should be led to that full, conscious, and active participation in liturgical celebrations which is demanded by the very nature of the liturgy, and to which the Christian people, “a chosen race, a royal priesthood, a holy nation, a redeemed people” (1 Peter 2:9, 4-5) have a right and obligation by reason of their baptism.The sacrificial nature of the Mass, solemnly defended by the Council of Trent, because it accords with the universal tradition of the Church, was once more stated at the Second Vatican Council, which pronounced these clear words about the Mass: At the Last Supper, Our Saviour instituted the Eucharistic sacrifice of his Body and Blood, by which the Sacrifice of his Cross is perpetuated until he comes again; and till then he entrusts the memorial of his Death and Resurrection to his beloved spouse, the Church.