Tony Blair's religion has long been one of the most straightforward and yet least understood aspects of his character. Such is the suspicion of religiosity among the liberal intelligentsia that it has been one of the sub-themes of criticism of him, especially over the Iraq war.
That suspicion lay behind Jeremy Paxman's question about whether Mr Blair and President Bush had prayed together in the approach to war.
The Prime Minister is buffeted between stereotypes: that American Christians are fanatically right wing and British Christians are pacifists. Neither caricature can be applied to Mr Blair, but religion has often been used to suggest that his values are somehow different from most people's, or that he is driven by a hidden religious calling.
In his early days in office, it was suggested that, because he was married to a Roman Catholic, he had secret Papist tendencies. The implication was that this explained why he was such a conservative on social issues.
The flaw in this reasoning is that Cherie has always been a liberal, left-wing Catholic. She is in favour of women priests and disagrees with the Vatican on contraception. On the subject of his belief, it is much simpler to take her husband at his word.
He is an ecumenical Anglican who dislikes setting boundaries between denominations and faiths. He says his belief in God became "practical rather than theological" when he was a student, and that "my Christianity and my politics came together at the same time". It is, therefore, never necessary to use religious language to describe his motives or to judge his actions.
But because he is a believer, he does sometimes use such language himself. He wanted to end his television address to the nation announcing his decision to send British forces into Iraq with the words "God bless you", but was prevailed upon by his advisers to end with "Thank you".
Peter Stothard, a former editor of The Times, who was a semi-official chronicler of this period, recorded the brief theological debate. Mr Blair complained: "You are the most ungodly lot I have ever ..." To which Peter Hyman, his speechwriter, who is Jewish, said: "Ungodly? Count me out." Someone else said: "That's not the same God." To which Blair replied fiercely: "It is the same God."
Two weeks later, with the invasion heading towards its conclusion, he told Mr Stothard in the Cabinet Room that he was ready "to meet my maker" and answer for "those who have died or have been horribly maimed as a result of my decisions".
Just as in his interview with Michael Parkinson, the language of God's judgement is a religious person's way of saying that the ultimate assessment of the right or wrong of his actions will not be for him to make. Non-believers would ascribe such a judgement to the collective wisdom of the people, or historians, or posterity. Believers, unless they are literalist fundamentalists, and Blair is not one of those, use a different formulation to express precisely the same idea.
The writer is a biographer of Tony BlairReuse content