Tommy Tiernan, Soho Theatre

In Irish mythology, a stray sod is an enchanted piece of grass that, if stepped on, leaves a person feeling disorientated and lost, even in familiar surroundings. Although there's no reference to this in Tommy Tiernan's new show, Stray Sod, there's plenty of self-knowing stage Irishness – even, briefly, Oirishness – as he delivers a riveting 80 minutes of comedy that's a sort of state-of-the-nation address about his home country.

Tiernan won the 1998 Perrier (now Edinburgh Comedy) award in 1998 for an intricately woven and beautifully delivered tale based on his Irish Catholic childhood; it heavily referenced philosophy, mythology and the Bible, and was utterly enchanting. He tours extensively in Ireland, where he's a huge star, makes equally successful forays into America and Australia, but is sadly only an occasional visitor to the UK. He's now 44, he tells us, and started drinking again two years ago after his wife and children told him he was so boring off the sauce that, after eight teetotal years, he went back on it.

Ah, alcohol and the stage Oirishness; while he doesn't quite say “begorrah” there are times when I fear it's not far from his lips; the Irish like a drink, they are connected to nature - “Did you ever listen to a field? At night?” he asks – but when he starts reciting the Mass in Gaelic he loses many in his predominantly emigrant or (like me) second-generation Irish audience. One of the emigrants heckles: “I haven't a clue what you're saying, Tommy.”

As the show goes on, it's increasingly obvious that Tiernan's view of Ireland is out of synch with the modern, pro-European and tech-savvy one I know, although his reference to a remote place on the island - “The nearest town is eight days away … by email” – is undoubtedly very funny. He hankers after a time when families waked their dead at home, talking about a grandfather “laid out on his own kitchen table, covered with sandwiches”, rather than taking them to the local funeral home and missing the craic.

He has much to say and packs a lot in - about fatherhood, mental health and Ireland's economic woes, among many other things - and it's an accomplished piece of delivery and writing, although I could have done without references to ugly women and "gyppos", and there's a weird insert of a Bob Dylan song. Each routine gathers in speed and volume and there are times when Tiernan is reminiscent of a preacher, a fire-and-brimstone one at that, so it comes as no surprise to learn that he once considered the priesthood but his disappointing Leaving Cert results meant the seminary turned him down.

The Leaving Cert reference, by the way, is one of many in Stray Sod that would go straight over the heads of anybody who doesn't have Hibernian blood in their veins. But, as the comic suggests, if you don't understand something he says, just join in the laughter if you see your neighbour enjoying a joke. He's right - the sheer force of his personality, as well as the widespread bonhomie in the room, will carry you along.

• Tommy Tiernan is at Soho Theatre, London W1 until 1 February, then touring the UK and Ireland until 2 May