Constantly receiving one another as sister Churches

In the last century especially, Anglicans have become more and more aware of the theological and spiritual resources of their brothers and sisters in the East; it is not too much to say that both the thinking and the piety of Anglicans would have been unrecognizably different without this growing and thankful awareness; and many of the ways in which we as Anglicans now seek a way forward for the unity and coherence of our own Communion have been shaped by the inspiration of the Christian East.

But in the last seventeen years, this instinct of common emphasis and purpose has been probed and tested at a new depth in the work of our International Commission for Anglican-Orthodox Theological Dialogue. The Commission has not sought to negotiate an agreed position between rival views; it has begun from first principles, reflecting at length on the foundations of the Church in the triune life of God and the interpenetration of divine and human nature in the incarnate Son, and has advanced from there to offer a fresh perspective on the challenges that we face today – within the Church itself and in relation to the world that is hungry for words of life from us. It is a document that seeks unashamedly to lay out the foundation for proclaiming good news to our world: a bold and inviting vision of God’s will for his Church that is more than just the record of an ecumenical encounter.

It reflects many dimensions of our indebtedness to the Orthodox theological perspective; and you, Your All-Holiness, have yourself been a powerful spokesman in East and West for many of the themes that come into focus here. You have taught us, as no other global church leader has, the imperative significance of a moral and spiritual understanding of our material environment as the natural outworking of our faith and participation in the communion of the divine persons. You have witnessed to the difficult task of holding diverse Christian communities together in charity and right doctrine without the sanctions of centralised control. And in this connection we are all sharply aware of how your leadership and witness is exercised in local circumstances of real difficulty and constraint. We wish to assure you of our strong support for you and your fellow – Christians in Istanbul and our continuing gratitude for your courage and clarity as a voice in the Orthodox world and in the Christian world in general.

Archbishop Rowan Williams Address at Evensong 30 January in the presence of the Ecumenical Patriarch, His All-Holiness Bartholomew I, and the International Commission for Anglican-Orthodox for Theological Dialogue

The reason for all this ecumenical malarcky?

The Church, although one, exists as Churches (in the plural), and these Churches exist as One Church in and through constantly receiving one another as sister Churches

John Zizioulas The Theological Problem of Reception