LUMEN GENTIUM – The Dogmatic Constitution on the Church

11. Taking part in the Eucharistic sacrifice, the source and summit of the Christian life, they [the faithful] offer the divine victim to God and themselves along with it. And so it is that, both in the offering and in holy Communion, in their separate ways, though not of course indiscriminately, all have their own part to play in the liturgical action. Then, strengthened by the body of Christ in the Eucharistic communion, they manifest in a concrete way that unity of the people of God which this most holy sacrament aptly signifies and admirably realizes. 26. They [bishops] diligently encourage and instruct their flocks to play their part, in a spirit of faith and reverence, in the liturgy and above all in the holy sacrifice of the Mass. 50. It is especially in the sacred liturgy that our union with the heavenly Church is best realized; in the liturgy, the power of the Holy Spirit acts on us through sacramental signs; there we celebrate, rejoicing together, the praise of the divine majesty, and all who have been redeemed by the blood of Christ from every tribe and tongue and people and nation gathered together in one church glorify, in one common song of praise, the one and triune God. 51. For if we continue to love one another and to join in praising the most holy Trinity—all of us who are children of God and form one family in Christ—we will be faithful to the deepest vocation of the Church and will share in a foretaste of the liturgy of perfect glory. 67. The sacred synod expressly teaches this Catholic doctrine and at the same time urges all the sons and daughters of the Church to foster generously the cult, especially the liturgical cult, of the Blessed Virgin, and to hold in high regard the practices and exercises of devotion towards her recommended by the teaching authority of the Church in the course of centuries, and religiously to observe those decrees laid down in the past regarding the cult of images of Christ, the Blessed Virgin and the saints.

Promulgated by Pope Paul VI on November 21, 1964, following approval by the assembled bishops by a vote of 2,151 to 5.

From: Vatican Council II: Constitutions, Decrees, Declarations. The Basic Sixteen Documents, General Editor: Austin Flannery, OP, Liturgical Press. One can purchase the entire book or individual documents as an eBook at Liturgical Press.