I was pleased with my idea for Good Friday: I would use Kirkwall’s hangman’s ladder to talk about execution by the state. Pretty good, eh?

Now, the primary purpose of Late Call was to give ageing punters a soothing word as they sat there in their slippers – or “baffies”, as we called them in West Fife – drinking their Horlicks before retiring contentedly to their northern bedchambers for a peaceful night. There was one wee problem, though. The lights in the cathedral made me look eerie, standing beside the gruesome 13-step ladder. The cadaverous electronic crofter, talking about death in a dark, Kierkegaardian way, spooked the aforementioned ageing punters.

Some pensioners, it was rumoured, died in their baffies. Those who did make it to their beds woke up ­screaming. Ach well.

So, given the train wreck in which my TV career crashed before it got started, I take my hat off to those who do television well. There is an art to it – and that is what lies at the heart of the spat between Professor Tom Devine and Neil Oliver, presenter of A History of Scotland on BBC1.

With his flowing dark mane and intense Jacobite looks, Oliver cuts a glamorous figure. Sellotape antlers to his heid and he’d be the Monarch of the Glen. I am firmly in the Devine camp, though. His book The Scottish Nation – which at one stage outsold Harry Potter – is excellent. In August I saw the good professor deliver a ­brilliant hour-long lecture on the Scottish Enlightenment before 600 people at the Edinburgh ­International Book Festival, all without a single note. It was a tour de force. Oliver’s TV series has been marked by dodgy graphics, dodgy hairstyles and, some have argued, dodgy history. Whatever. To my mind, Devine is the more substantial man – and I’m not talking about waistlines here.

If you want to see real state-of-the art televised history, though, try to take in Professor Diarmaid ­MacCulloch’s six-part A History of Christianity on BBC4. The fourth ­episode is due to be screened this Thursday evening. ­MacCulloch, ­professor of the history of the church at Oxford University, is a world-class historian who is much admired by Catholic and Protestant historians alike, as well as by academics who don’t give a gnat’s left testicle about religion. Not only that: without being youthful or glamorous, he exudes brio, chutzpah and style. He knows his stuff and he knows how to engage an audience. This is television for grown-ups, serious education for consenting adults. No clever-clogs graphics, no brooding in the mist: just an outstanding academic at the top of his game, with a compelling televisual presence.

Mind you, the subject matter is terrific. The underlying question is this: how did a tiny Jewish sect led by a country preacher who was executed by a combination of religious and civic powers become a dominant shaper of western ­civilisation? Whatever one believes or disbelieves, the story of the rise of the Christian Church is truly astonishing. The ­journey from persecuted ­minority cult to official religion of the

Roman Empire, with Popes ­crowning emperors, could not have been predicted. Whether Constantine’s adoption of Christianity was actually good for the Church is still a matter for debate; what is beyond doubt is that the western – indeed, the world – story cannot be understood without a grasp of the full range of Christianity’s influence.

The presence, for good or for ill, of what Terry Eagleton calls “the richest, most enduring form of popular culture in human history” is profound, even in its alleged absence in some places.

Accident of history or the result of divine providence? Historians have to deal with the former, but if they insist that it cannot, literally cannot, be the latter, they are moving into the area of secular dogmatics. Diarmaid MacCulloch, television’s non-­celebrity star, is worth watching, with or without the baffies.