Unitatis redintegratio

The title of the document is taken from the opening words of the Latin text. The opening words of the official English translation are: "The restoration of unity among all Christians is one of the principal concerns of the Second Vatican Council."

Description

Unitatis Redintegratio calls for the reunion of Christendom and is similar to a previous call for unity by Pope Leo XIII in his 1894 encyclical letter Praeclara gratulationis publicae and by Pope Pius IX in his encyclical In Suprema Petri Apostoli Sede. However, Unitatis articulates a different kind of ecclesiology from Praeclara. It focuses on the unity of the people of God and on separated Christian brethren rather than insisting according to the classical formulation that schismatics must return to the fold under the unity of the Vicar of Christ.

Unitatis acknowledges that there are serious problems facing prospects of reunion with Reformation communities that make no attempt to claim apostolic succession as the Anglican communion does. Ecclesial communities which adhere to Calvinism are a particularly challenging case because they and Catholicism have important doctrinal differences on key issues such as ecclesiology, liturgy and mariology. Other communities have insoluble doctrinal differences with Catholic Christianity because their theology of the Holy Trinity is manifestly incompatible with the doctrine as articulated by the council of Nicaea in the early Church.