If we are to look at the teaching of Vatican II on Christian Unity, I think we can also see how it is lived out in the ordinary life of the Catholic Church - and this is its most profound implementation - and not just in explicit acts of ecumenical dialogue or shared prayer and activity. The Focolare Movement, with its specific charism of unity and in which Fr Leahy has a strong engagement, and the charism of prayer for Christian Unity of the Bridgettine Sisters are two examples. The prayers of the Church's liturgy are another example.
Among the Collection of Masses of the Blessed Virgin Mary is a Mass of "Mary, Mother of Unity". The Collect of that Mass indicates a foundation for the unity of the Christian Church in the unity that exists between all of the human race:
All-holy Father,In the third edition of the Roman Missal, there are three Masses included under the title "For the Unity of Christians", with a total of six Collects. This title is of itself interesting, suggesting as it does that the primary unity to be sought is that between Christian people, and that the structural unity of different Christian Churches and communities is sought as a means to that first end. It is interesting to read all six Collects, and recognise in them different aspects of the Catholic Church's understanding of the idea of the unity of Christians.
fountain of unity and wellspring of harmony,
grant that all the families of nations,
through the intercession of the Blessed Virgin Mary,
mother of the human race,
may be gathered together
to form the one people of the New Covenant.
The first draws attention to the significance of Baptism as a first, and in the view of Pope Benedict when he addressed leaders of other Christian denominations in Cologne in 2005 underestimated, foundation for unity among Christians:
Almighty ever-living God,Another echoes the theme of the Collect of the Mass of "Mary, Mother of Unity":
who gather what is scattered
and keep together what you have gathered,
look kindly on the flock of your Son,
that those whom one Baptism has consecrated
may be joined together by integrity of faith
and united in the bond of charity.
O God, who have united many nations in confessing your name,These two prayers clearly refer to a unity in faith, that is, a unity in the content of what is believed. This is of the essence of how the Catholic Church understands unity among Christians, so those communities that are based on a kind of federation of Christians who believe different things and believe that it is the successful maintenance of this kind of balance of differing views that constitutes unity, have a very different understanding than does the Catholic Church.
grant us, we pray,
the grace to will and to do what you command,
that the people called to your kingdom
may be one in the faith of their hearts
and the homage of their deeds.
Several of the six Collects are explicit in reference to prayer for overcoming divisions between Christians, some with an emphasis on striving for unity and others with a more explicit emphasis on overcoming division. The one cited below also draws attention to the adverse effect of division among Christians on the Church's evanglising mission.
Look with favour on your people, Lord, we pray,A final thought. Just as Baptism is seen as a foundation for unity among Christians belonging to different Churches and communities, so can martyrdom - that is, witness to the point of the offering of one's life - be seen as an expression of unity among those separated Christians. Pope John Paul II expressed it like this in his encyclical Ut Unum Sint n.84:
and pour out upon them the gifts of your Spirit,
that they may grow constantly in love of the truth
and devote themselves with zeal
to perfect unity among Christians.
Make known in us, O Lord
the abundance of your mercy
and, in the power of your Spirit,
remove the divisions between Christians,
that your Church may appear more clearly
as a sign raised high among the nations
and that the world, enlightened by your Spirit,
may believe in the Christ whom you have sent.
I have already remarked, and with deep joy, how an imperfect but real communion is preserved and is growing at many levels of ecclesial life. I now add that this communion is already perfect in what we all consider the highest point of the life of grace, martyria unto death, the truest communion possible with Christ who shed his Blood, and by that sacrifice brings near those who once were far off (cf. Eph 2:13).[UPDATE/ASIDE: The homily that I heard at Mass this Sunday reminded me of the Catholic Church's teaching that the unity of Christ's Church has not been lost - there is still one Church and it is to be found visibly in the Roman Catholic Church - but that Christians have become divided from it in different ways and to different extents. Whilst other Churches and communities might not consider the Roman Catholic Church to be the unique place of the unity of the Church, they can nevertheless share the principle that the unity of the Church itself has not been lost and that it is the unity of Christian people we seek in the commitment to ecumenism. This is respected by the terminology of prayer "For the Unity of Christians". It also provides a basis for each Christian Church or denomination seeking to be ever more faithful to its Christian belief as an aspect of work for the unity of Christians. As Pope Benedict XVI indicated in Cologne - I can't find my original post as I write, but it is reproduced here - there can be a surprising proximity of ideas expressed in different language when different Churches or communities manifest their own belief in an honest way.]