Second Vatican Council
The Second Ecumenical Council of the Vatican, commonly known as the or , addressed relations between the Catholic Church and the modern world. The council, through the Holy See, was formally opened under the pontificate of Pope John XXIII on 11 October 1962 and was closed under Pope Paul VI on the Solemnity of the Immaculate Conception on 8 December 1965.
Sacrosanctum Concilium
Sacrosanctum concilium, the Constitution on the Sacred Liturgy, is one of the constitutions of the Second Vatican Council. It was approved by the assembled bishops by a vote of 2,147 to 4 and promulgated by Pope Paul VI on 4 December 1963. The main aim was to achieve greater lay participation in the Catholic Church's liturgy. The title is taken from the opening lines of the document and means "this Sacred Council".