Tis the season not only for comfort food but for comfort reading.

This is not the time to embrace Finnegans Wake or any other books designed to do your head in. We need something welcoming, unchallenging and, most of all, familiar. In short, we need The Thirty-Nine Steps by John Buchan (pictured).

When I first read what its author described as a "shocker" I cannot recall, but it must have been some time ago. I have a set of Buchan's oeuvre, in a dinky edition that Thomas Nelson published in a blood-red binding. I bought it from McNaughtan's second-hand bookshop in Edinburgh's Elm Row. It is, I am happy to report, one of the few bookshops of my youth which is still with us and still luring me.

However, the edition of The Thirty-Nine Steps I read recently was published by Everyman's Library and adorned with illustrations by Edward Ardizzone. The novel first appeared in 1915 when the bells were constantly tolling for the fallen in the First World War. Buchan wrote it the previous year, when it was serialised in three parts in Blackwood's Magazine under the pseudonym H de V; even Andrew Lownie, Buchan's biographer, does not know why this name was chosen. Apparently, Buchan also suggested an alternative title –The Kennels Of War –which, thankfully, fell by the wayside.

Quite why The Thirty-Nine Steps achieved the success it did is bemusing. Such is often the way with bestsellers. My own theory with regard to these is that once they begin to sell, they achieve word-of-mouth momentum which is as hard to stop as a rolling snowball. In his evergreen study, Bestseller, Claud Cockburn mentions The Thirty-Nine Steps en passant, recalling that he read it as an 11-year-old, when he assumed it "mirrored more or less accurately the general facts and atmosphere of adult life". When later it was pointed out to him that this was not the case, it took him "a long time to find out by experience and observation that 'real' life was a lot more like that than I had been told it would be".

What strikes you today when you read the novel is that it tests to the utmost your ability to suspend disbelief. As children we read without expectation or cynicism or preconception. Children open a book and follow it whichever way it flows. All the writer need do is hold their attention. I say "all" but that is no easy task, especially in this age when the competition is so severe. That said, as JK Rowling demonstrated, children do not make that daft distinction between old and new media. What they're interested in is what seizes their imagination and in that regard I doubt books will ever be superceded.

I would love to know what 21st-century 11-year-olds think of The Thirty-Nine Steps. Lownie calls it "picaresque". Once Richard Hannay goes on the run in Scotland, with the aim of killing time before returning south and unmasking those behind a conspiracy "to get Russia and Germany at loggerheads", the novel offers one set piece after another. The Hollywood equivalent is the car chase but, in Buchan's hands, the pace is more sedate if just as improbable and dependent on coincidence.

You daren't stop reading because, if you do, you'll see holes in the plot the size of Mars. Then there is the anti-semitism, accusations of which have dogged Buchan since his death in 1940. So casually is it introduced that the author's best defence is surely that he was reflecting his times. Nevertheless it makes uncomfortable reading now. Which is a pity because there is much to enjoy in a tale that has echoes of Stevenson's Kidnapped. Like its heroes, David Balfour and Alan Breck, Hannay is a man for the hills and moors which offer escape, cover, adventure. Once upon a time I tried to retrace his footsteps but, like him, they were long gone.