O Bishops! O Gas and Gaiters! O feet jammed into ecclesiastical mouths! In this redemptive season, naivety on the part of one bishop from one denomination might be politely ignored, like an inadvertent burp. When two are at it there is no choice. Anybody who believes that religion involves more than words must say so.

For two bishops — the Rt Rev Tom Burns, Roman Catholic Bishop of the Forces, and the Anglican Bishop of Rochester, the Rt Rev Michael Nazir-Ali — have praised President Mahmoud Ahmadinejad’s showy release of our naval hostages. Both seem dazzled by the tricksy Holocaust-denying President, formerly best known for wanting his neighbour Israel “wiped off the map”. But one mention of Easter and religion and the churchmen forget all that, and roll over in delight. Bishop Burns says the Iranians’ faith is “exemplified by their good deeds. They are offering to release the sailors and Marines not just as a result of diplomacy but also as an act of mercy in accordance with their religion.”

Bishop Nazir-Ali — slightly less crazily — did at least acknowledge that both sides were acting from “mixed motives”. He did not specify exactly what Britain’s motives were mixed with, but praised the way the Iranians acted “within the moral and spiritual tradition of their country” and contrasted this with Britain’s “free-floating values” and our Government’s failure to say anything religious or “anchored in a spiritual and moral tradition”.

Well, if the devil can quote scripture, so can a poor despairing hack. To both bishops I can only say “Beware of false prophets, which come to you in sheep’s clothing, but inwardly are ravening wolves . . . A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit. Wherefore by their fruits ye shall know them.” Or, to quote the rather less sacred Mandy Rice-Davies: “Well, President Ahmadinejad would say that, wouldn’t he?”

The cynicism of the Iranian leader’s lip-service to Easter and forgiveness should not need underlining. When Bishop Burns says they “put their faith into action to resolve the situation”, he ignores the fact that Iran caused the damn situation. They snatched seafarers who were not in their waters — even by their own original GPS positioning — and held them for a terrifying fortnight while mobs howled for their blood. They threatened them with years of prison unless they told lies on camera. From distant RE lessons I seem to remember that forcing other people to break the Commandments is considered even worse than doing it yourself.

When Bishop Nazir-Ali commends Iran’s “moral and spiritual tradition” he forgets that the prisoners were isolated and blindfolded, even after the farewell handshake; interrogated under bright lights, lined up to face a wall and frightened by the cocking of weapons. With Islam in his own family background he should perhaps also think about Leading Seaman Faye Turney, stripped to her knickers and told that the others had gone home and she was alone; in that context he might recall that the Koran’s fourth chapter enjoins: “If ye be kind towards women and fear to wrong them, God is well acquainted with what ye do.” Indeed in justice to all good Muslims it must be said that the game-playing cruelty of the last fortnight offends Islam as much as it breaches international law. You can explain it politically — by fear, by weakness, by the awful backwash of the awful Iraq war — but not religiously. No way.

When contrasting Iran’s behaviour with “free-floating” British morality, the bishop could pass the time counting on his fingers the Commandments broken by his Eastertide hero: false witness has definitely been borne, sending gear to Iraqi bombers who kill civilians, nurses and peacekeepers hardly observes Thou Shalt Not Kill; and as for stealing, we have yet to get back the boats and equipment seized in the 2004 incident, let alone this one. I am not too happy about the MoD encouraging the sailors to sell their stories, but at least the details will clarify the public mind about the Pharisaical hypocrisy of the Easter release.

What the bishops are betraying is a kind of desperation in the churches: a sense that when the battle for the public culture is being lost, you clutch at any straw, however filthy. They express delight at President Ahmadinejad’s disingenuous mention of religion simply because he did mention it. As Bishop Nazir-Ali says: “The President talked about the religious background to the release, with reference to the Prophet’s birthday and the passing over of Christ. What struck me was that if there were any values on the British side, they were free-floating and not anchored in a spiritual and moral tradition.”

If? If? A bit harsh. Our own Government is not perfect, by a long chalk, and I have opposed the war in Iraq from the very start; but in this case I do not see it as a sign of loose morality that Mr Blair stuck to respecting the “history and tradition” of Iran rather than waffling about God. Britain had simple enough values in the past fortnight — a desire to keep young people alive and to uphold international law. Rather better values, indeed, than those which led us into the Iraq war in the first place. But it is mad for churchmen to expect politicians in a mainly secular society to witter about the Resurrection during diplomatic negotiations. You don’t have to be Richard Dawkins to grasp that.

If there really are bishops who think that governments should spout religiosity at all times, they are howling for the moon. More seriously, if they think that larding a religious gloss on to cruel, illegal, manipulative behaviour makes it all right, they are edging towards a position which can only — with a cautious shudder — be defined as evil.

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