A couple of weeks ago, a nurse stood beside my hospital bed with a pen and a clipboard. After the questions about allergies and next of kin came the one about religion. None, I said, when she asked which one. Her English was hesitant. "You are … what do you call it … an atheist, then? Shall I write that?" "Please just write 'none', or 'no religion'," I said.

I don't know why I jibbed at the word atheist. It may have been Jonathan Miller's argument that non-belief in God is a narrow and entirely negative self-description that ignores all the other things you might either believe in or not, from homeopathy through necromancy to the Gaia theory. As a definition it belongs to the same dull category as "non-driver" or "ex-smoker"; not driving or no longer smoking, just like not believing in God, is an inadequate guide to the self. There are so many richer and more positive ways, or so you hope, to summarise your behaviour and beliefs and what you might add up to when the counting is done.

But after the nurse left with her questionnaire, I wondered about other motives for denying a truth about myself. Had it to do with social cowardice, or some ridiculous notion of politeness on my part? Three other men shared my bay in the ward, and who knew what beliefs they held? "Atheism" has such a scorning ring to it. I wouldn't have wanted them to think (though, of course, they wouldn't have cared less) that, as I lay beside them, I was quietly cackling at their misplaced faith in the other life to come. As it turned out, two of them may have declared at least the name of such a faith to the nurse, because the next day a visitor came into the ward and made a beeline for their beds, and talked briefly and earnestly to each man in a low voice.

The men were originally from Mayo and Dublin (I wrote about Joseph last week), and I can say only that their visitor seemed like a missionary woman, or my idea of one. She had cropped grey hair, a blue cardigan and flat shoes, and she looked like someone who ate sparingly and cared for God very much.

This visit, too, had a consequence. A priest came next. He may have been an Anglican or a Roman Catholic. As there was no religious content in what he said, and as I have a poor knowledge of clerical uniform, it was hard to know which. "How are you feeling? I don't want to disturb you when you're needing rest. It's good that you're feeling stronger, or so the nurses tell me. I'll be off now and leave you to your tea."

That was more or less what he said to each man. They nodded in return, and then the priest backed away.

Of all the people who came near our beds in any official capacity, he was the most deferential. What you might call the carer-patient discourse in a British hospital is marked by a certain robust chumminess. You hear all kinds of surprising things. A young nurse from Essex will put her arm around an elderly Muslim and tell him to "Cough it up, Abdul sweetheart, cough it up." An equally young woman doctor of good Indian parentage will ask: "Any trouble with the old waterworks?" as though she had stepped out of Carry On Corporal. But the priest seemed to have found no way of introducing his specialism, the awkward subject of God, even as a euphemism.

Perhaps it wasn't the right time. Perhaps that time would be later. As things stood, what Tony from Mayo and the Londoner in the next bed hungered for wasn't religion, but tobacco.

They were in their 60s, with bad lungs. Soon after breakfast, Tony would begin to agitate for a porter who could put him in a wheelchair and take him down in the lift to street level, where he could join a dozen others in a row on the pavement outside, smoking and staring at the traffic in the Euston Road. If no porter was available, then Tony would fret till the afternoon, when a visiting relative would wheel him away for an hour or so. The doctors went pretty easy on him. They gave a harder time to the Londoner, who, in between his trips to the pavement, had regular bottles of oxygen.

"You've just got to co-operate and stop smoking, otherwise you're going to be in hospital until you die," I overheard the consultant telling him, which is as grim and certain a prognosis as you can hear. But the Londoner – let's call him Ted – seemed not to hear it. According to him, all that being told not to smoke did was to make him smoke more: "It's the stress you see, doctor."

"In any case," as he said later, "I'm not going to stop smoking so that they can make money out of me." "They" were the hospital and, according to Ted, who may well have been right, the hospital was rewarded for every patient it turned into an ex-smoker. But why didn't he want the hospital to make a little more money? After all, it was looking after us rather well. "Because it was built on one of them lend-lease deals," Ted said, meaning one of the largest PFI schemes in England, "and the government was stupid and got taken for a ride." So Ted's position, as I understood it, was that he'd continue to curtail his life because to do otherwise would be in some minute way to subsidise a public-private partnership of which he disapproved.

This was probably no more than a labyrinthine excuse for the next John Player Special, but in its notions of foolish self-sacrifice ("He was a martyr to his cigarettes") Ted's conversation had a religious dimension that I never heard anywhere else in the hospital. Talking with him reminded me of the arguments I used to hear on the doorstep when anyone called with a Bible in their hand and my father got at them with his ferocious knowledge of scripture that had been acquired in his youth at Baptist Sunday school. My father was of a generation that imbibed God, took him seriously, and then found him wanting. Books by the Rationalist Press and the Thinker's Library (with Rodin's Thinker in profile on the spine) stretched across a shelf of his bookcase and promised the joys of atheism, agnosticism and an open mind.

If he were alive now, I think he would be surprised that writers such as Richard Dawkins and the late Christopher Hitchens had become famous partly through their attacks on religion. The New Atheism? Surely those intellectual battles had been fought and won long ago – even by the 1960s, my father had found it hard to find a door-knocking Christian who was properly equipped for a decent debate. Resurgent Islam and America's evangelical Christianity may provide a new focus for atheism – hence Dawkins and Hitchens – but here in Britain, believers move among us with diminished power, more shyly and uncertainly, so that it almost seems rude to say "atheist" in the kindness of a hospital ward. Not that I am not one, you understand – among other things.