Once again the sage Maimonides, often cited for his scholarly wisdom, is in no doubt where he stands on this issue: 'It is a positive commandment to destroy the seven nations, as it is said: Thou shalt utterly destroy them. If one does not put to death any of them that falls into one's power, one transgresses a negative commandment, as it is said: Thou shalt save alive nothing that breatheth.'

Unlike Maimonides, the children in Tamarin's experiment were young enough to be innocent. Presumably the savage views they expressed were those of their parents, or the cultural group in which they were brought up. It is, I suppose, not unlikely that Palestinian children, brought up in the same war-torn country, would offer equivalent opinions in the opposite direction. These considerations fill me with despair. They seem to show the immense power of religion, and especially the religious upbringing of children, to divide people and foster historic enmities and hereditary vendettas. I cannot help remarking that two out of Tamarin's three representative quotations from group A mentioned the evils of assimilation, while the third one stressed the importance of killing people in order to stamp out their religion.

Tamarin ran a fascinating control group in his experiment. A different group of 168 Israeli children were given the same text from the book of Joshua, but with Joshua's own name replaced by 'General Lin' and 'Israel' replaced by 'a Chinese kingdom 3,000 years ago'. Now the experiment gave opposite results. Only 7 per cent approved of General Lin's behaviour, and 75 per cent disapproved. In other words, when their loyalty to Judaism was removed from the calculation, the majority of the children agreed with the moral judgements that most modern humans would share. Joshua's action was a deed of barbaric genocide. But it all looks different from a religious point of view. And the difference starts early in life. It was religion that made the difference between children condemning genocide and condoning it.

In the latter half of Hartung's paper, he moves on to the New Testament. To give a brief summary of his thesis, Jesus was a devotee of the same in-group morality — coupled with out-group hostility — that was taken for granted in the Old Testament. Jesus was a loyal Jew. It was Paul who invented the idea of taking the Jewish God to the Gentiles. Hartung puts it more bluntly than I dare: 'Jesus would have turned over in his grave if he had known that Paul would be taking his plan to the pigs.'

Hartung has some good fun with the book of Revelation, which is certainly one of the weirdest books in the Bible. It is supposed to have been written by St John and, as Ken's Guide to the Bible neatly put it, if his epistles can be seen as John on pot, then Revelation is John on acid.¹⁰⁰ Hartung draws attention to the two verses in Revelation where the number of those 'sealed' (which some sects, such as the Jehovah's Witnesses, interpret to mean 'saved') is limited to 144,000. Hartung's point is that they all had to be Jews: 12,000 from each of the 12 tribes. Ken Smith goes further, pointing out that the 144,000 elect 'did not defile themselves with women', which presumably means that none of them could be women. Well, that's the sort of thing we've come to expect.

There's a lot more in Hartung's entertaining paper. I shall simply recommend it once more, and summarize it in a quotation:

Lest it be thought that the exclusiveness of traditional Judaism is unique among religions, look at the following confident verse from a hymn by Isaac Watts (1674–1748):

What puzzles me about this verse is not the exclusiveness per se but the logic. Since plenty of others were born into religions other than Christianity, how did God decide which future people should receive such favoured birth? Why favour Isaac Watts and those individuals whom he visualized singing his hymn? In any case, before Isaac Watts was conceived, what was the nature of the entity being favoured? These are deep waters, but perhaps not too deep for a mind tuned to theology. Isaac Watts's hymn is reminiscent of three daily prayers that male Orthodox and Conservative (but not Reform) Jews are taught to recite: 'Blessed are You for not making me a Gentile. Blessed are You for not making me a woman. Blessed are You for not making me a slave.'

Religion is undoubtedly a divisive force, and this is one of the main accusations levelled against it. But it is frequently and rightly said that wars, and feuds between religious groups or sects, are seldom actually about theological disagreements. When an Ulster Protestant paramilitary murders a Catholic, he is not muttering to himself, 'Take that, transubstantiationist, mariolatrous, incense-reeking bastard!' He is much more likely to be avenging the death of another Protestant killed by another Catholic, perhaps in the course of a sustained transgenerational vendetta. Religion is a label of in-group/out-group enmity and vendetta, not necessarily worse than other labels such as skin colour, language or preferred football team, but often available when other labels are not.

Yes yes, of course the troubles in Northern Ireland are political. There really has been economic and political oppression of one group by another, and it goes back centuries. There really are genuine grievances and injustices, and these seem to have little to do with religion; except that — and this is important and widely overlooked — without religion there would be no labels by which to decide whom to oppress and whom to avenge. And the real problem in Northern Ireland is that the labels are inherited down many generations. Catholics, whose parents, grandparents and great-grandparents went to Catholic schools, send their children to Catholic schools. Protestants, whose parents, grandparents and great-grandparents went to Protestant schools, send their children to Protestant schools. The two sets of people have the same skin colour, they speak the same language, they enjoy the same things, but they might as well belong to different species, so deep is the historic divide. And without religion, and religiously segregated education, the divide simply would not be there. From Kosovo to Palestine, from Iraq to Sudan, from Ulster to the Indian subcontinent, look carefully at any region of the world where you find intractable enmity and violence between rival groups. I cannot guarantee that you'll find religions as the dominant labels for in-groups and out-groups. But it's a very good bet.

In India at the time of partition, more than a million people were massacred in religious riots between Hindus and Muslims (and fifteen million displaced from their homes). There were no badges other than religious ones with which to label whom to kill. Ultimately, there was nothing to divide them but religion. Salman Rushdie was moved by a more recent bout of religious massacres in India to write an article called 'Religion, as ever, is the poison in India's blood'.¹⁰¹ Here' s his concluding paragraph: