John Rentoul: As God is his witness, Tony Blair did not say what some people think he said

Talk about a no-win situation. Alastair Campbell, the Prime Minister's press secretary, once jokingly said, when he rejoined an American journalist in the middle of an interview with Tony Blair: "Is he on God? We don't do God." Ever since, this trivial remark has been elevated to the status almost of doctrine, and constantly repeated. This has the effect of portraying Blair's faith as a sinister purpose, hidden from public view by anxious spin-doctors. The impression was reinforced by the revolt of the advisers when Blair wanted to end his television address to the nation at the start of the Iraq war with "God bless you".

The idea that Blair's handlers try to stop him doing God feeds in turn into anti-war sentiment that cannot accept the Prime Minister's given reasons for joining the invasion and so looks for other, concealed, motives. That is why the combination of God and Iraq is so convulsive. It is not news that Blair is a Christian - and it is utterly conventional for Christians to say that God is ultimately their judge. But for those people, many of whom work for the BBC, looking for ulterior motives that explain what is to them the inexplicable decision to go to war, religion is the key.

There was a similar kerfuffle last October when George Bush was reported as saying, "God told me to invade Iraq", on the basis of a conversation he had had with a Palestinian leader. Again, it was a case of religious language meeting secular assumptions, with a little transatlantic culture clash thrown in. It was not surprising that President Bush should have used a theistic, world-faiths idiom in conversation with a Muslim, who then gave an account of the conversation in rather more emphatic terms. Nor, unfortunately, that his words were seized on as evidence that President Bush is a crazed religious zealot.

The British have always viewed the religiosity of American politics with effortless superiority, and tend to regard explicit references to religion in their own politicians as evidence of simple-mindedness. When Margaret Thatcher delivered a lecture on her theology to the General Assembly of the Church of Scotland, this was considered a monstrous arrogance. Alastair Campbell knew this, but Blair knew it too. He once got into trouble for suggesting that Christianity and Conservatism were incompatible. What he had said was that his religion and his politics were two aspects of the same coin - a rather unremarkable confession but one which seems to cause endless confusion.

The idea that Blair is some kind of religious crank who has to be restrained by his minders from spilling forth his weird world view does not survive a moment's thought. He does not need Campbell to warn him of the dangers. In last night's interview with Michael Parkinson, Blair's own hesitation was obvious. Although he has said it before - telling Peter Stothard, the former editor of The Times that he was ready to "meet his maker" to answer for the Iraq war - he did not intend to do it again. Not because he is trying to hide something, but because he knew that his words would be reported in precisely the way that they were. But he used the word "faith" when asked how he coped with such a difficult decision, and Parkinson, who knows a thing or two about interviewing, jumped in to ask what he meant.

He was then asked if he prayed, praying being, to too many non-believers, a particularly suspect activity in the same category as hearing voices, speaking in tongues and the live sacrifice of the first-born. "Well, I don't want to get into something like that," said Blair, truthfully. He did not want to give the BBC the excuse to interview Reg Keys, the father of a soldier killed in Iraq, and to report the less than surprising news that he is still opposed to the war. He did not want to trigger another wave of commentary based on thoughtless stereotypes of Christians. Stereotypes that are not only crude but also contradictory. On the one hand Christian zealotry is supposed to have driven Bush and Blair to war in defiance of reason; on the other, Rose Gentle, another bereaved parent, says "a good Christian wouldn't be for this war".

But if it is simply good Christians versus bad Christians, then the language of religion is simply another way of rehearsing the same arguments about the war that everyone knows so well. For God read history. For Christianity read morality. For prayer read serious contemplation of the ethical basis of action. A non-believer should not have the slightest trouble understanding Blair's religion in those terms.

All of which was fairly clear if you watched the whole interview, in which Blair explained how his religion and his politics crystallised at the same time, when he was a student. But the Prime Minister said "God" twice. and that was enough to rerun the anti-war case yet again. Which is curious, because there was much in the interview that was new. Such as the fact that Blair watched football on television without the sound because he does not know what a mute button is. Or, indeed, his decisionto go on Parkinson at all.

That decision gave something valedictory to the performance. Certainly, there were wistful backward glances. "It was an honour ever to do the job," he said. He talked about how he had had to "harden" himself to the effect of decision-making and how few people know what it is like. But it would be a misreading of Blair to think that a discursive interview on a mass-audience chat show signals the beginning of his summing-up. On the contrary, the attempt to renew his connection with the wider, "non-political" electorate is testament to his determination to carry on. In his continuing balancing act between offending Gordon Brown and asserting his popular mandate from last year's election he came up with a new formulation. "I said I'd serve a term and that's what I'll do." But he did not say "full term", as he did in his speech to the Labour conference last autumn. He only said, "Yeah, I've always said that" when asked if he meant a full term.

A lot of the reporting of his obsession with his legacy, as with his religion, is more a reflection of the obsessions of journalists than a representation of reality. If Blair looked back, it was only because Parkinson asked him to. Indeed, the legacy serves much the same purpose as the religion. Because some people disagree so passionately with Blair - about the war, or schools policy - they look for hidden motives. If it is not his Christianity, it must be his desperate desire to secure a legacy worth having in the short time that is left. In a saner world, people might watch the Parkinson interview and judge Blair on what he said rather than on why they think he said it.