Almost 2,500 bishops will ultimately attend as council fathers, joined by several hundred auditors and advisers.
1962 — The first session
From Oct. 11 to Dec. 8, the first session of the council meets, and work begins in 16 commissions for the 16 documents to ultimately come out of the Second Vatican Council.
These cover many topics, including the collegiality of bishops, the relationship with other religions and religious freedom, as well as a number of key themes in four documents called constitutions (more on those below).
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1963 — A new pope
On June 3, Pope John XXIII dies at age 81. Within three weeks, a successor, Pope Paul VI, is elected.
The new pontiff promptly announces the council will continue. Therefore, from Sept. 29 to Dec. 4, the second session gathers in Rome.
Just before, Paul VI also announces a reform of the Roman Curia.
Issued on Dec. 4, Sacrosanctum concilium, the Constitution on the Sacred Liturgy, calls for the use of Latin “to be preserved in the Latin rites” but also allows for the use of local — vernacular — languages in some areas.
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1964 — The Light of the Nations
From Sept. 14 to Nov. 21, the council fathers gather to continue their work.
On the final day of the year’s session, Lumen gentium, the Dogmatic Constitution on the Church, is issued, among other documents.
This text on the “Light of the Nations” proclaims that the laity “carry out for their own part the mission of the whole Christian people in the Church and in the world.”
Also on the final day, Nov. 21, Pope Paul VI announces that the eucharistic fast will be reduced to one hour.
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