The Second Vatican Council's Decree on Ecumenism (Unitatis Redintegratio) staked the cause of Christian unity clearly on the ground of Church renewal.
Taking its cue from Pope Paul VI's opening address to the second session of Vatican II, it even said – twice – that the Catholic Church shared in the blame for "sins against unity."
The pope's and the council's seeking of forgiveness for Catholic sins against other churches was likely the first of what has become a feature of post-Vatican II Church life – the ecclesial apology.
This was a major advance in Catholic thinking. The original text of the Decree on Ecumenism put forward by the Secretariat for Christian Unity made no mention of a confession of Catholic guilt.
To that point in time, only the guilt of others had been recognized. For the document to talk about the Church's need to confess the sins of Catholics might well have resulted in its being shunted into the waste bin of history.
It was Pope Paul VI who put the issue on the table when, in his address opening the second session of Vatican II, he spoke of the need for mutual forgiveness.
One might want to know why the final text of the Decree on Ecumenism is not more specific. Generally, when one asks for forgiveness it is for some specific wrong that one has done and is acknowledging. Apologies that begin, "If I did something to offend someone, . . ." are generally a long way from perfect contrition.
However, a statement of an ecumenical council is not meant to exercise a judgment on individual historical events, judgments that can easily change when more evidence comes to light.
A statue of Jan Hus, a church reformer who was burned at the stake in 1415, a century before the Reformation, stands in the Old Town Square in Prague, Czech Republic.
As well, the decree makes clear it is not judging contemporary events, but rather those that occurred 400 or more years earlier. It is saying not that the Church itself was guilty of something, but rather that individual Catholics had done wrong. It is one thing to apologize for your own actions and quite another to seek forgiveness on behalf of someone long dead.
The essential thing is that the council admitted that guilt for the original separation existed on both sides and said that Protestants today are not guilty of bad faith because they are not in full communion with the Catholic Church.
So, where do we go from here? Perhaps the most important statement of the decree is, "There can be no ecumenism worthy of the name without interior conversion" (UR 7). Theological dialogue is "absolutely required" (UR 9), but the soul of the movement toward greater Church unity is spiritual ecumenism.
There must be institutional renewal, renewal through which each Church increases its fidelity to its own calling (UR 6). The council sees this renewal as already occurring through the biblical and liturgical movements, the apostolate of the laity, Church social teaching and new forms of religious life.
Also, there must be personal conversion. On this point, the decree quotes Ephesians 4.1-3, in which St. Paul begs his fellow Christians "to lead a life worthy of the calling to which you have been called, with all humility and meekness, with patience, forbearing one another in love, eager to maintain the unity of the spirit in the bond of peace."
The living of a holy life moves the Church toward greater unity. If it was the sins of individuals that shattered Church unity, it will have to be holiness that restores unity. When all Christians live in perfect humility and strive to maintain the unity of the spirit, full Church unity will not be far away.
Still, we are left with the issue of institutional renewal. Often, such renewal comes through the action of the Holy Spirit such as in the growth of the new movements to which the decree referred. Yet, there must also be processes of self-reflection leading to deliberate steps that ensure the Church is increasingly faithful to its calling.
The renewal of the Church involves changing its own internal culture so that its structures reflect the call to dialogue, holiness and solidarity with the world that is evident throughout the Vatican II documents.
This does not happen overnight. Nor is it the case that once the Church undergoes renewal, the process has come to an end. The Church's internal culture must always be under renewal so that it increasingly reflects the Gospel.
It took the Church well over 100 years to implement the decrees of the Council of Trent in the mid-16th century. No doubt it will take as long to fully implement Vatican II. Old ways die hard even when there is good will. And it will take time to arrive at clarity at how to best implement the council's principles.
However, of one thing we can be sure – that as institutional and personal renewal take place, the Church will move ever closer to the fullness of unity.
(Some information in this article came from Johannes Feiner's commentary on the Decree on Ecumenism in the series of commentaries on Vatican II documents edited by Herbert Vorgrimler.)