For my sermon this morning, I am returning to the subject of the second most important churchman in Britain, John Sentamu, the Archbishop of York. You may know that, alongside such luminaries of the spiritual world as Katie Price and Nancy Dell'Olio, the Archbishop appeared as a columnist in the first edition of The Sun to be published on the Sabbath.

It was called "Sentamu's Sunday Service" and it wouldn't be doing the thrust of his column too much of an injustice to say that the Archbishop was suggesting that Rupert Murdoch was doing God's work by publishing "our country's favourite paper" seven days a week. Sentamu's people were quickly on the defensive: their man was merely pointing out that The Sun was Britain's highest-circulation newspaper, and he had not yet decided whether his offering would be a regular fixture.

Not that it should worry a man as close to Godliness as Sentamu, but I was disappointed with both the fact and the substance of his contribution on Sunday: he effectively exhorted his followers to go forth and buy The Sun seven days a week. He is, of course, entitled to his view, and in any case we are used to one or other of our voluble Archbishops on any number of subjects, from gay marriage to celebrity culture, from climate change to sexual politics. But I wonder, as the revelations piled up about The Sun's alleged wholesale corruption of the police and of public officials, whether Sentamu, pictured, had pause for thought, and reflected on whether his breathless interpretation of appearing in the paper as "a fantastic honour" was indeed the expression of a wise man.

My sense of letdown, however, is a little more profound. In 2003, I had the honour (yes, right word) of introducing Sentamu – then the Bishop of Birmingham – before he gave the Longford Lecture, an annual discourse on the subject of crime and punishment. He spoke so eloquently, so passionately, so coherently and the central message of his speech – that restorative justice, a process in which parties to a specific offence, perpetrator and victim, work together on dealing with the aftermath of the offence and its implications for the future, will create a more harmonious society – was so utterly persuasive that, from my standpoint, it didn't brook argument.

He told the story of how, outside the Stephen Lawrence inquiry, he confronted an angry mob and told them to put their weapons away. "Violence is not the answer," he said. "We don't believe in God," they snarled back. "It doesn't matter," Sentamu replied, "because God believes in you." They didn't have an answer to that.

His speech was moving and illuminating by turn, and it was almost enough to make me turn to religion. And now, fast forward nine years, he's endorsing a newspaper whose idea of rebalancing the justice system is to swing towards retribution rather than restoration, and has an attitude to immigration that doesn't speak of compassion and may not be in sympathy with a man who fled Uganda for the sanctuary of Britain. There is another reason why Sentamu's Sunday Service disappointed me. We were told that the launch of another paper was good news for journalists, given that so many have lost their jobs recently. In which case, why not have columnists doing the columns, and leave the Archbishops to sermonise elsewhere?

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