The Second Vatican Council did not lay down a clear path to final unity, but it did give the ecumenical movement a framework. Pope Francis is using the same framework but taking a different approach to that of his predecessors

It was, significantly, during a ceremony to mark the last day of the (then named) “World Octave of Prayer for the Unity of Christians” that Pope John XXIII, on 25 January 1959, announced his intention to convene an ecumenical council. Among the purposes of the council was “to invite the separated communities to seek again that unity for which so many souls are longing in these days throughout the world”.

At the time, the official Catholic position envisaged unity being achieved through a “return” of separated Christians to the Roman Catholic Church. By the end of its third session in 1964, however, the Second Vatican Council had moved to a very different way of conceiving the path to Christian unity. Such a shift was achieved through a reconfiguration of the Catholic imagination regarding the relationship between the Catholic Church and the separated Christian Churches and ecclesial communities. 

In finding a way through the impasse of centuries, four overlapping notions were particularly important: the notion of “elements of the Church”; a more nuanced way of understanding the relationship between “the Church of Christ” and “the Catholic Church”; a re-framing of Catholic ecclesiology in terms of the notions of “communion” and “degrees of communion”; and the affirmation of a necessarily tensive relationship between unity and diversity.