The road from Lambeth Palace to the Vatican is reasonably well travelled these days. George Carey, as Archbishop of Canterbury, met Pope John Paul II six times. Dr Rowan Williams was in Rome for the inauguration of Pope Benedict XVI last year and is expected to return later this year for his first official audience with John Paul’s successor. But the history of such meetings is relatively brief. Until 1960 no Archbishop of Canterbury had visited a Pope for more than 500 years. The previous Primate of All England to call, Thomas Arundel, in 1397, was a fugitive. Such visits may now be an irregular part of an Archbishop’s calendar, but in no sense is Dr Williams’s journey run of the mill. It takes place at a critical time for the Anglican Church, and much depends on the rapport he is able to establish with Pope Benedict.

Dr Williams has two interlinked problems. The mood in his 77 million flock ranges from unease to barely suppressed rebellion. The long-existing disagreements over homosexuality, brought bitterly into the open by the consecration of Gene Robinson as Bishop of New Hampshire three years ago, have threatened to shatter the ideal of one broad church and replace it with a collection of fragments. Anglo-Catholic congregations appear to be thriving. African and Asian churches are mutinous. The liberal wing that successfully pushed for the ordination of female and gay vicars wants further reform. To resort to political rather than theological parlance, such internecine strife hardly makes the Anglican Church an attractive partner for the Catholic Church.

The result has been to plunge the atmospherics of the ecumenical movement into mid-winter. The installation of Pope Benedict was interpreted as a setback for relations. He, after all, as the Vatican’s rigid guardian of doctrinal orthodoxy, produced documents suggesting that Anglican ordinations rendered it an improper Church, and that other religions were inherently defective. Pessimists would advise Dr Williams to pack a thick overcoat whatever the month of his visit.

In fact, a little optimism may not be undue. Pope Benedict’s mind is not as closed as his critics would like to suggest. He has made Christian reunification one of his priorities. Indeed, it is gently suggested by some that the Pope’s previous uncompromising stance may have had more to do with his predecessor than his own instincts. His first moves, such as his overture to Judaism, would support this. In wishing to advance the laudable cause of ecumenism, Dr Williams may not be banging on an eternally closed door.

When he visited the late John Paul, Dr Williams wore the episcopal ring that Pope Paul VI had given to Archbishop Michael Ramsey in 1966. Such gestures doubtless help to create warmth. But Dr Williams needs to generate more than soothing mood music. He will have, no less, to convince the Pope of the relevance of the Church of England, and persuade him that a dialogue is worth pursuing. His balancing act is to do so without suffering further strife within his own ranks, a difficult but not impossible task. Though the goal of two churches reconciled is a lofty one, Dr Williams may be well advised to look for progress at street level. In terms of faith, unity cannot be imposed from above. Progress will come when different congregations practise mutual understanding and acceptance. At that moment, winter will give way to spring.