Sacrosanctum Concilium, 4 December 1963
The constitution on the sacred liturgy, and the first document the council promulgated. It teaches that the liturgy, above all the Eucharist, is the summit and the source of the Church's whole life, and calls for the full, conscious, and active participation of all the faithful in it. The constitution permits a measured use of the vernacular languages alongside Latin, orders the revision of the rites of Mass, the sacraments, the Divine Office, and the liturgical year for greater clarity and simplicity, and gives directives on sacred music, art, and church architecture as servants of worship.
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