So, the Mother Superior calls all the nuns together and says to them: "I must tell you all something serious. We have a case of gonorrhoea in the convent."

So, the Mother Superior calls all the nuns together and says to them: "I must tell you all something serious. We have a case of gonorrhoea in the convent."

"Thank God," says an elderly nun at the back of the room, "I'm so tired of Liebfraumilch."

Funny or not? Yes, surely. Offensive? Probably only to the National Front for the Protection of Teetotal Nuns. Here's another tale: a Protestant man saw a woman standing on a bridge, preparing to jump. He ran over to her and pleaded with her not to do it. "Are you Catholic or Protestant?" he asked her.

"Protestant," she replied.

"Me too," he said.

"Are you Episcopalian or Presbyterian?"

"Presbyterian."

"Me too. Are you Church of Scotland, Free Church or Associated Presbyterian Church?"

"Church of Scotland."

"Me too. Do you come from the UP or the UF tradition?"

When she said, "UP," he snarled, "Die, heretic scum."

I like it, but it's a bit too near the truth to be comfortable. Like the old one about a shipwrecked Proddy on a deserted island who built two churches - one to attend, one to stay away from on a matter of principle.

Now how about this? The Three Wise Men, on camels, arrive at a tumbledown abode. They go in, put down their expensive gifts and prostrate themselves before a newborn child, much to the bafflement of the bairn's watching single mother. Minutes later, they come back angrily and snatch the gifts away. Wrong hoose.

What I've just described is the opening scene of Monty Python's Life of Brian, a satire about a hapless Jewish man who is born in the same era and location as Jesus of Nazareth, is mistaken for the Messiah and is crucified. The film is to be shown at the Glasgow Film Theatre, nearly 30 years after an application for an AA certificate - the equivalent of the current 15 rating - was turned down by Glasgow City Council. In 1980, demonstrators cried "blasphemy" in Sauchiehall Street outside the cinema where councillors were attending a private screening. The late Pastor Jack Glass roared that the film "crucified Christ afresh" and thrust three nails at the licensing committee chairman.

I first saw The Life of Brian in Toronto in 1980, at the time when the Glasgow decision was making headlines. I thought it was very funny, with great lines like "He's not the Messiah, he's a very naughty boy", and, "Apart from the sanitation, medicine, education, wine, public order, irrigation, roads, the fresh water system and public health, what have the Romans ever done for us?" Then there was the batty scene in which the Judean People's Front slugged it out with the People's Front of Judea.

The film is a classic, which has been voted into the top three funniest films ever. Not everyone is pleased. Stephen Green, the havering director of Christian Voice, said: "It is a bit of a shame it's been granted a licence in Glasgow, but it shows how much we have let standards slip." Mustn't overdose on happiness. As the Jewish Woody Allen - Judaism is much more relaxed about humour than the other monotheistic religions - points out: "Life is full of misery, loneliness, and suffering - and it's all over much too soon."

There's nothing quite so fearsome as a deeply offended Christian (other than, perhaps, a deeply offended Muslim, but it's a close-run thing.) This is a pity, because satire is an honourable part of the Judeo-Christian prophetic tradition. Iconoclasm helps clear away a lot of junk, kitsch and idolatry. Brilliants like Jonathan Swift and Soren Kierkegaard sent up conventional religion to distinguish between what really matters and what is just noise. Mind you, the Church does a pretty good unintentional job of sending itself up. There are the verbal errors, like the over-enthusiastic preacher who shouted to the heavens: "Let everything that hath breasts praise the Lord!". Or notice board howlers, such as: "The sermon this morning: Jesus Walks on the Water.' The sermon tonight: Searching for Jesus.'"

A long overdue welcome to Glasgow, John Cleese and friends.