By a vote of five to two, we agreed to exclude the Christian from our fortnightly dining club

Sarah has let us all down. Only a week after we had agreed that she would be a valuable member of our fortnightly dining club, she turned up at our planning meeting in The George and casually announced that she had decided to become a Christian.

Geoff could hardly contain his exasperation. "But only a couple of years ago, you were running around telling everyone that you were a bleeding Buddhist." Sarah was ready for him. "I was not a 'bleeding Buddhist'. I simply told you that I was searching for some meaning in life and had been considering Buddhism. All that's happened is that I have continued my search and found what I was looking for in Christianity."

You could feel the tension around the table. How could any of us look forward to debating contemporary political issues at our fortnightly dinners when we knew that there was someone present whose idea of redistribution was coloured by the miracle of the loaves and fishes, and whose sense of the future was not so much bounded by the next election as the prospect of eternal life?

As is usual at such moments, Mike tried to be conciliatory. "What exactly do you mean when you say that you're a Christian? You're surely not one of those Christians who believe in angels and Jesus being the Son of God. You mean you're a metaphorical Christian. You believe that Christ had a lot of valuable things to say, but that his basic teaching has been contaminated by a lot of metaphysical mumbo-jumbo."

Sarah refused the lifebelt. "No, I'm not a metaphorical Christian. Any more than you were once a metaphorical Trotskyist, or any more than Geoff is currently a metaphorical supporter of Sheffield United. In fact, I rather relish what you call metaphysical mumbo-jumbo. At least Christianity has a certain internal logic, which is rather more than can be said for the feeble attempts that most of you have been making over the past five years to find some residual elements of socialism in new Labour."

From then on, it was open season. No sooner had Jane dealt at length with some of the feminist and gynaecological issues raised by the concept of the Immaculate Conception than Geoff was piling in with rather more historical detail than was strictly necessary about the excesses of the Crusades. There was a brief lull as Mike sympathetically invoked William James on the validity of religious experience, but then Andy, in typical relativistic mode, wanted to know how on earth it was possible for someone like Sarah, who had studied a variety of world religions, to conclude that only one enjoyed unique access to the truth.

It was fearfully one-sided. Sarah did manage to suggest that the Immaculate Conception was a rather more credible concept than the dictatorship of the proletariat, and that the victims of the Crusades were somewhat less numerous than those of the Holocaust. But when she rounded on Andy and tried to argue that relativity was synonymous with moral nihilism, we all realised that there was only one way left to save our dinner club. By a vote of five to two, we agreed, there and then, that Sarah should be excluded from our club until such time as she either abandoned Christianity or came to view it with the sort of thoroughgoing scepticism that was compatible with contemporary debate.

She was remarkably affable about her exclusion, even buying a complete round of drinks before saying goodbye and wishing us well in our discussions. But as Geoff muttered after she had left: "That's the way with Christians: show the other cheek, always holier than thou." That made us all feel a great deal better.