Masked by the drama of a controversial and tense papal visit to a leading Muslim nation, an unexpected thaw seems to be taking place in relations between the Roman Catholic Church and the Eastern Orthodox world, which were broken apart by the Great Schism of 1054. Pope Benedict's visit to Turkey was originally in response to an invitation from the Ecumenical Patriarch Bartholomew I. The invitation was a distinctly positive move so soon after Benedict's election, and is further evidence that this Pope is regarded more warmly by the Orthodox than his predecessor. Encouraging noises are even coming out of Moscow, which Pope John Paul II failed to be invited to visit despite his eagerness to do so.

Two factors count in the present Pope's favour when dealing with the Orthodox, where Russians still dominate: that he is German, not Polish, and that he has expressed theological opinions that the Orthodox were glad to hear. In fact there was no sign that John Paul II's Polishness influenced his attitude to the Orthodox Churches. Nor is it apparent that Cardinal Ratzinger differed significantly from John Paul in relation to these matters. They both seemed willing to take an eirenic approach to the filioque controversy - the Orthodox complaint that the wording of the Nicene Creed was unilaterally altered by Rome despite the Creed's adoption by an ecumenical council. There was agreement that the Creed without the filioque clause was a true statement of Catholic doctrine, notwithstanding that Orthodox theologians have been less willing to make the complementary concession.

There are other grievances not yet dealt with, such as the status of the Uniate Churches (Churches loyal to Rome that use the Orthodox liturgy), whose existence is regarded as an act of papal aggression. These quarrels would melt in the morning mist if the fundamental divide between the Orthodox and Catholic Churches were overcome. It centres on the papacy itself, and its claims, formalised by the First Vatican Council in 1870 but historically of much longer standing, to infallibility and universal jurisdiction throughout the Church.

One of the most celebrated sayings of Professor Joseph Ratzinger before he became Archbishop of Munich was that "Rome must not require more from the East with respect to the doctrine of primacy than had been formulated and was lived in the first millennium." This implied that Orthodox reception of papal primacy, always a condition for unity, did not mean acceptance of these nineteenth-century expressions of it. It also implied that the Orthodox would have to drop their view that these doctrines were heretical, and that is not so easy to imagine. But if there is any theologian in the world able to steer through these minefields it is the present Pope, and that is part of his appeal to the Orthodox.

Repairing the Schism would alter the geopolitical balance between Christianity and the Muslim world rather more fundamentally than any papal visit to a Muslim state, however successful. Unity of witness in a combined Church of 1.5 billion souls would be a source of authority and confidence, despite some scaling down of the power of the Vatican in order to bring it about. Of course a thousand years of history will not be overcome in a year or even a decade: but it is the next thousand years that matter more.