Ramadan has started, and in Istanbul there have been readings of the Quran in the ancient Church of Hagia Sophia for the first time in 80 years. The Greek government is furious. Its foreign ministry released a statement condemning the move and saying: "Obsessions verging on bigotry with Muslim rituals in a monument of world cultural heritage are incomprehensible and reveal a lack of respect for and connection with reality." It added: "Such actions are not compatible with modern, democratic and secular societies." A former Greek foreign minister, Dora Bakoyannis, said the readings "virtually transformed it into a mosque for the first time in 80 years. It is a provocative and incomprehensible act and shows disrespect against Orthodox Christians across the world and is not in line with Turkey's European course."
The Greeks are obviously furious. Do they have a point, or are they over-reacting?
Taking the long view, just arguably. Hagia Sophia is one of the oldest and greatest church buildings in the world, dating back to AD 537. To give you an idea of its antiquity, some of the graffiti on its walls is in Viking runes. But it became a mosque in 1453 when Constantinople, as Istanbul was then, fell to the Ottoman Turks. It was secularised in 1931 and became a museum. So it was a church for 916 years, but a mosque for 478 years. But the Greeks still probably do have a point.
And the point is?
For one thing, life is very hard for the Greek Orthodox population of Turkey, which is small, poor and faces discrimination at various levels. It's continually faced with reminders of its great and glorious past, of which Hagia Sophia is the prime example. It is an absolutely breathtaking building which is full of history. You can go inside and stand where Byzantine emperors were crowned for nearly a thousand years. They know it will never be a church again, though a museum is better than a mosque. But it also has a symbolic value: keeping it as a museum is a sign of Turkey's commitment to secular, democratic values which include everyone rather than privileging the majority Muslims.
Would it be fair to say that Turkey is going down a particular route, in that respect?
It would indeed. Its current prime minister Recep Tayyip Erdogan has pushed an Islamising and highly authoritarian agenda. He has clamped down on the freedom of the press, taking action against people who have criticised him personally. Erdogan has denied wanting an Islamic constitution for Turkey and publicly defended secularism, a tradition now deep-rooted in the country since its imposition by the revered Kemal Ataturk. But his protests are not universally believed.
But why is Hagia Sophia such a sensitive issue?
It's being made so by right-wing nationalists, who see it as a way of asserting Turkishness against the world. Some have genuinely religious reasons, too; it's regarded as a sacred building by many Muslims. The question comes up periodically. Last year Turkey's culture and tourism minister Yalçın Topçu said that reopening Istanbul's iconic Hagia Sophia as a mosque is his "personal dream, my goal, my ambition".
And there are dangerous undercurrents of nationalism: on May 29 this year, the anniversary of the Ottoman conquest, an imam led prayers in front of the building and a crowd of young people demonstrated, chanting: "Let the chains break, open Hagia Sophia."
And what is the Greek Orthodox Church saying?
Nothing in public, as far as I know. The Patriarch of Constantinople is known as the Ecumenical Patriarch and is first in prestige among all the Orthodox Churches. However, he has nothing like the influence in Turkey that Patriarch Kirill does in Russia. Behind the scenes, though, there will be frantic diplomatic activity.
But I think the Turks have a pretty strong hand.
The Turks can ignore anything Europe says. Turkey is in a diplomatically stronger position than it has been for centuries, because it can turn on or off the flow of migrants to Greece, and therefore into Europe, at will (though others make it from Libya, of course). The migrant crisis has led to governments tottering all over the continent, the possible break-up of the EU and the rise of really nasty far-right parties.
Is there any country with influence over Turkey?
Possibly Russia, which oddly enough is not a favoured destination for migrants and whose Patriarch is hand in glove with President Putin. The Orthodox Holy and Great Council is to start shortly and Hagia Sophia will certainly be on the agenda, if only in private.
Back to whether this row is justified. It's only a few prayers.
It's the symbolism that matters, to both sides. As an example of how sensitive it is, an experiment was done by Stanford University aimed at capturing the precise acoustic qualities of Hagia Sophia, with the aim of being able to recreate the exact sound of Byzantine chant in a modern concert hall. But actually performing Byzantine chant in Hagia Sophia, for the first time since 1453, was deemed politically impossible, so the researchers had to develop a different method using balloon pops.
So prayers are the thin end of the wedge. Unless it's made clear to the Turkish government that this isn't acceptable, it will be seen as a green light for turning it into a mosque again. The 1931 decision marked progress; this could only be a backward step. And it's not as if Istanbul is short of mosques.
Is Hagia Sophia really all that special?
It's a bit shabby, but if you have any kind of historical imagination, yes. When Vladimir of Ukraine was looking for a new religion back in AD 987, he sent his envoys to Constantinople. They reported back from Hagia Sophia: "We knew not whether we were in heaven or on earth. For on earth there is no such splendour or such beauty, and we are at a loss how to describe it. We know only that God dwells there among men, and their service is fairer than the ceremonies of other nations. For we cannot forget that beauty.
"Every man, after tasting something sweet, is afterward unwilling to accept that which is bitter, and therefore we cannot dwell longer here."
Follow Mark Woods on Twitter: @RevMarkWoods