“Not much of a showman,” commented one visitor to the Vatican last week as we watched Pope Benedict XVI conduct a prayer service with the Archbishop of Canterbury in the papal chapel.

He meant the Pope, not Dr Williams: but then, the Archbishop is not expected to wow the crowds, whereas Benedict — the former Cardinal Joseph Ratzinger — is constantly measured against the extraordinary pontificate of his predecessor, John Paul II, a former actor who played to the world gallery with consummate skill.

Pope Benedict, by contrast, is not much of a traveller: since he succeeded John Paul a year and a half ago, he has twice been to his native Germany (he is a former Archbishop of Munich), to Spain and to John Paul’s native Poland, but that’s about it. His trip to Turkey starting tomorrow will be the supreme test of his ability to withstand the global spotlight. Although the visit started out as a journey of Christian reconciliation with the Orthodox Church, the agenda shifted to the confrontation with Islam after the Pope’s incautious remarks about the Prophet Muhammad in Germany this summer. The word in Rome is that the Pope will be wearing a bullet-proof vest.

The comparison with John Paul is in any case unfair. For a start, Pope Benedict is getting on — he will be 80 next March — whereas Cardinal Karol Wojtyla of Poland was an athletic 58 when elected in 1978. And Benedict is not actually that bad at handling a crowd: I have watched him many times in St Peter’s Square beaming, joking and moving with ease among the faithful.

The reputation he acquired as “God’s rottweiler”, as guardian of Vatican doctrine, is something of a caricature. He campaigned against liberation theology in Latin America and described homosexuality as an “intrinsic evil” — but so did John Paul. He joined the Hitler Youth in his native Bavaria at the age of 14 — but so did many other young Germans, and his family was anti-Nazi. He was drafted into an anti-aircraft battery at 16, but deserted.

He loves the “dressing up” side of being Pope, donning old-fashioned satin and ermine-trimmed headgear and robes at any opportunity, not to mention dainty Prada shoes. In many ways he has been misread: in private he is shy, warm, thoughtful. His first encyclical, Deus Caritas Est, was about love, sexual and otherwise. He plays the piano well, with a preference for Mozart.

More a difference of style than of substance with John Paul, then. But in today’s world, image is all. Last week he said he was publishing a book about Jesus earlier than planned “because I do not know how much time and strength remains to me”: when elected he said he was “a humble worker in the vineyard of the Lord” and asked for God’s help. He will need it in Istanbul.