The Pope rattled lots of cages the other day when he expressed support for Amazonian bishops who will be discussing married clergy at their synod next year. This magazine examined the development last week, suggesting that many conservative Catholics were supporters of the notion of a married clergy, not least because of the example set by the priests of the Ordinariate of Our Lady of Walsingham – married, Anglican clergy who are perfectly legitimate Catholic priests. But there’s one glaring problem with the prospect of a married clergy, which is rarely addressed. Ordaining married men is, if you like, a return to the status quo ante, the state of things before the Gregorian reforms of the 11th century and, indeed, to the example of the Apostles. (It’s worth remembering that, according to the Synoptic Gospels, Christ healed Peter’s mother-in-law, but we hear precisely nothing about his wife.) But ordaining a vir probatus – or man of proven worth – the situation that the Pope raised in an interview with the German paper Die Zeit in March, is one thing; allowing ordained priests to marry is quite another. Let me clarify: it is a mere matter of discipline whether to ordain already married men, but for already ordained priests to marry is a radical break with tradition. Yet the end result is the same: priests with wives and possibly families. The distinction between the two situations is completely understood in the Eastern Churches. A Lebanese friend, whose niece is married to a priest, says that prior to ordination young seminarians run around looking for a suitable wife before the die is cast and they are ordained. It’s too late then to marry. But in the Eastern churches, the higher vocation is to the monastic life and it is monks who get to be bishops. A bit like the Church in the 4th century, really. So if you are a Copt or a Maronite, you know perfectly well that married men get to be priests, but priests do not get to marry. In the Roman West, we have a similar situation for deacons: we can ordain married men as deacons, but once their wife dies, that’s it: they can’t take another. Now try imagining how you are going to explain the distinction to a sceptical British public. How do you tell people that the reason the parish priest is now persona non grata is that he’s run off and got married to the parish secretary; but that the assistant priest, who is also married but already had a wife before he was ordained, is absolutely fine? It’s a tricky one. And if it’s tricky to explain to Catholics, it’s even more problematic trying to explain the distinction to a secular public, which, in England, is used to the Anglican model of clergy who can marry pretty well at will. In fact, in the West the entire model of a married clergy was upended by Luther, who made a polemical point by marrying an ex-nun, having been a friar himself. Once Francis has crossed the Rubicon and approved the ordination of viri probati in the Amazon, it’s pretty much open season for married clergy elsewhere, already ordained or not. I once asked the late Cardinal Cormac Murphy-O’Connor how he would deal with this if, say, a sceptical John Humphrys were to ask him on the BBC’s Today programme what was wrong with priests marrying if married men could become priests. He agreed it would be an impossible argument to sell. Yet he was one of the champions of the notion that if you ordain married men the celibacy problem could be dealt with. Is this a deal-breaker? It’s certainly an awfully big problem. If the word goes out that the Catholic Church is fine with married clergy, I don’t see how we’ll hold the line on only ordaining married men. Already, we have ordained Anglican clergy quite legitimately as Catholic priests, even if some were bachelors when they were ordained. Interestingly, Mgr Keith Newton, the head of the ordinariate, told me that he was already married when he became an Anglican clergyman. When he explained as much to cradle Catholics, their hostility to him decreased. If we go down the route of ordaining mature married men, we’ll have to do an awful lot of explaining to the rest. It’s going to be tricky in terms of the subliminal psychology of the laity too, which can be summed up with my granny’s observation: “Protestant priests don’t have to give anything up, do they?” Dead right. There is a sacrificial aspect to ordination in the Catholic Church that is completely absent in the Anglican. And some at least of our tie to priests comes from the consciousness that they have given up something important for us. Melanie McDonagh is comment editor of the Evening Standard