The Weekend's Television: Christianity: A History, Sun, Channel 4Demons, Sat ITV1

The evangelical organisation Jews for Jesus aims to get all Jewish people to convert to Christianity. In the first episode of Christianity: a History, Howard Jacobson was travelling in the other direction. Jesus for Jews, you might call his project, since what it aimed to do was to reclaim the pale Galilean as a bar-mitzvah boy, inalienably the product of Jewish culture and religion. And while this isn't really a contentious idea for anyone prepared to think about it dispassionately, nearly 2,000 years of Christian theology have been devoted to fudging the fact, and, much worse, to demonising the people who made Christ what he was. "For Jews, Christianity has been, all things considered, a calamity," said Jacobson, recalling from his own childhood the instinctive flinch the symbols of the faith could produce: "We feared the cross as any vampire might... the crucifix encapsulated all our troubles."

Pious Christian faith – as you might gather from this – doesn't seem to be a necessary qualification for taking part. That's because the series isn't quite what the title suggests. This isn't a part-work history, through-composed by someone with a seat in divinity. It's a collection of pointedly personal essays, loosely arranged around the evolving chronology of the Church. Next week, Michael Portillo talks about the politics of the early Christian Church in Rome, and later in the series Ann Widdecombe beards Ian Paisley in his den to advance her view that the Reformation might have been better conducted, a meeting I confess I look forward to with a decidedly un-Christian relish.

That particular doctrinal spat is still some distance away, though. Last night, Jacobson had the subject to himself, and though he dismissed the claims for Christ's divinity as a bit of first-century spin-doctoring, designed to cover the embarrassing fact that a Messiah shouldn't end up executed like a common criminal, he didn't lack respect for Christ himself. He was, he said, "a man extraordinary for the dark, riddling powers of his expression, for the magnificently scornful sweep of his mind", which made Christ sound rather like a sublime op-ed columnist. Jacobson is no slouch himself when it comes to "scornful sweep", as readers of this paper will know, though it seemed a little restrained here, as if the subject of Christian anti-Semitism and centuries of self-righteous persecution were too grave for knockabout fury. St Paul was one of the principal villains – a classic case of the lethal, holier-than-thou zeal of the late arrival – but after him came a long line of pious demonisers, always ready to find gospel sanction for an outbreak of murder-the-neighbours. "It is essentially Oedipal," Jacobson suggested. "The younger religion in terror of the older, cruel, parental religion," and he ended with a unmistakably heartfelt plea to the Christian viewer: "Acknowledge it," he said. "Acknowledge that this Jewish religion... travestied for 2,000 years... is the foundation of all that you believe." I don't believe either, old or new, but the kinship is surely undeniable.

Jews were often represented in medieval woodcuts as literally demonic, with horns growing out of their heads, and a washy residue of such kind superstitious bestiaries is what animates Demons, a strikingly pointless bit of gothic flummery for Saturday evenings. It concerns Luke, who's recently discovered that he is the great-grandson of the famous vampire-hunter Abraham Van Helsing and, with the help of his dad's old friend, has been activated as a kind of otherworldly pest controller. This week, he was tracking down Gilgamel, a demon who looked like he was the front man for a particularly dim-witted heavy-metal band, and who had been abducting children, intoxicated by the odour of sanctity the little poppets give off. Philip Glenister plays Luke's mentor, Galvin, with an American accent that can only be Satanic in origin, and various fine British character actors pop up here and there, though not before taking the precaution of putting on demonic prostheses that make them effectively unrecognisable. I guess it's the thespian equivalent of pulling a nylon stocking over your head before you do a bank job. You really need the cash, but you'd prefer it if nobody can identify you later.

I confess I can't really see the point of these things, even when they're done with wit, as Buffy the Vampire Slayer was (though curse it to eternity for spawning so many bad imitators). You can find more unnerving and interesting examples of malevolence on any sink estate or in any corporate boardroom. And certainly Gilgamel turned out to be absolutely rubbish at demoning, eventually being vanquished with a hard stare and a single thrust from a red-hot sword, although he did do that demon trick of making everyone talk ye olde English first. "Turn and face me or I shall surely smite thee," shouted Luke, and then, rather unfairly, smote him anyway. I'm tempted to say it was diabolical, but that would be greatly to exaggerate its impact.