In the last 12 months, Elton John, Ozzy Osbourne, Neil Diamond, Kiss and the grizzled remnants of Lynyrd Skynyrd have announced end-of-the-road tours. Paul Simon has already embraced the sound of silence with a final show in September in New York while fellow Sixties luminary Joan Baez is also packing away the touring set list for good.

But for all those happy to exit stage left after decades of strutting vanity, there are still others who continue to rage against the dying of the light and the onset of their twilight years. Mick Jagger, Keith Richards, Robert Plant, Neil Young and Bob Dylan are still rocking well into their eighth decade, having long ago sold their souls for rock ‘n’ roll in some kind of Faustian pact.

It’s hard to imagine James Paul McCartney making a deal with the devil to prolong a career that now stretches back 61 years to the day he first met a fellow teenager called John Lennon on hallowed ground at a church fete in Liverpool. But a rummage around his attic for a Dorian-Gray type image might offer up a clue.

On Friday, December 14, the former Beatle brings his Freshen Up tour to Glasgow’s SSE Hydro, the latest staging post of a 24-show itinerary that takes in America, Japan and Europe. By the time it reaches its climax next June in Phoenix, McCartney will have turned 77.

A born performer, the musician has never met a stage he didn’t like. Still driven by a relentless work ethic, he steadfastly refuses to surrender to the notion that it might be time to finally hang up his famous Hofner bass and swap the life of a pensioner rock star for a rocking chair. It’s a subject that occasionally rankles. He prefers instead to still consider music more as a hobby than anything approaching the nine-to-five.

“I was talking to Willie Nelson, about this whole retiring thing, because he’s older than I am, even,” he said. “And he says, ‘Retire from what?’ And I think that just says it. Retire from what?”

The only concession to the march of time has been to finally let the grey in his hair grow out. Other than that, it’s business as usual and business this year has reaped a particularly bountiful harvest. A media blitz for Egypt Station, his 17th solo album, was rewarded with impressive reviews and brought him his first American Number One in 30 years.

And it was followed by the 50th anniversary reboot in November of the Beatles’ White Album, which again showcased the imperishable legacy of his old compadres and the unbreakable chains of his ever present past.

His Carpool Karaoke with James Corden saw him visiting childhood haunts in Liverpool and introduced him to an entirely new audience of millennials. According to YouTube, the footage has been seen by 35million people.

In September he took over New York’s Grand Central Station for a surprise show that literally did stop the traffic. And now here he is hitting the boards once again, maintaining the kind of pace a man half his age would do well to muster.

Rumours persist of a headline-grabbing appearance at Glastonbury next year. His Scottish gig comes 55 years after the Beatles first played in Glasgow at the Odeon and his first since Hampden in 2010, but oddly it will be only his ninth concert appearance overall in a city he once name-checked in the song Helen Wheels.

McCartney has been famous at an unimaginable level longer than nearly anyone else alive. To put an astonishing life into context, he wrote Yesterday, the world’s most covered song, in 1964 when he was just 22 years of age. He was a Fab Fab Four millionaire by the time he was 24 at a time when the Treasury was trousering 95 old pennies from every pound he earned and is today unchallenged as the world’s richest musician with a fortune estimated to be not far south of a billion pounds.

The legacy of his songwriting alliance with Lennon continues to shimmer down the decades; Deezer last week revealed more people under the age of 25 currently stream Beatles tracks than those who would have been around in their Sixties pomp. And the legacy of his prodigious post-Beatles output with Wings and his solo output garners more plaudits as the years tick down.

Lionised by his contemporaries and younger artistes, McCartney remains the epitome of rock ‘n’ roll Mozart, a musician whose work will endure for centuries. Throughout the Beatles’ career, he blunted Lennon’s sharp cynicism with an indefatigable optimism, a trait that often mirrored his media image as wacky, thumbs-aloft Macca.

There have, though, been plenty of tears in the rain. He was scarred by the death of his mum Mary – the hymn-like subject of Let It Be – from breast cancer when he was just 14. He slipped into a post-Beatles funk at his Argyle farm on the Mull of Kintyre before being pulled out of the blackness by his wife Linda.

Lennon’s dreadful assassination at the hands of a deranged fan in 1980 saw McCartney retreat to the margins – he turned his back on touring for nine years. His 29-year marriage to Linda was tragically ended by cancer in 1998 before the same illness claimed the life of fellow Beatle George Harrison three years later.

We’ll gloss over the mis-step of his subsequent marriage to the former model Heather Mills and the toxic – and expensive – aftermath that was played out so dramatically in the divorce courts. Today, McCartney is happily married to third wife Nancy Shevell, a publicity-shy American who provides the reassuring comfort blanket for a man who has never been without a female companion since the age of 16.

He takes enormous pride in his four children – the youngest from his marriage to Mills – and an extended family that also includes eight grandchildren. Yet there remains a sense that McCartney has been underestimated by history, a man who, despite his undoubted musical genius, is in his own way as insecure and vulnerable as Lennon was his seeming total opposite.

Music continues to nurture and nourish his life. But his most recent work has caught a man looking wistfully in the mirror and perhaps reading the runes of his own mortality. And this sombre self-examination is played out in the first track on his latest album, his voice frail and aged. On “Yesterday,” he sounded like a wounded youth. On “I Don’t Know,” he naturally sounds like an older man, his vocals now able to convey sadness not as an effect but as a fact.

His voice was once one of music’s most powerful instruments, as potent in its own way as Jimmy Page’s guitar or Clarence Clemons’ saxophone. But the debacle of his sub-par performances at the closing ceremony for the 2012 Olympics and the Queen’s Diamond Jubilee the same year handed critics a gilt-edged cudgel. The court of public opinion also delivered a damning verdict.

McCartney’s response was simply to circle the wagons behind the band that has been the mainstay of his live shows for almost 20 years and carry on regardless. The high notes are unquestionably harder to hit but he remains dedicated to his craft, in and outside the studio.

His 2015 collaboration with Kanye West and Rihanna on the song FourFiveSeconds may have mortified traditional fans but it gained him kudos with a new audience. (One famous tongue-in-cheek tweet congratulated the controversial rapper for giving new talent a break.)

These days more than any other McCartney seems to take shelter in the solace of live shows, as if the stage still offers an escape route from life’s problems. On another Egypt Station track, he wistfully talks about having been “broken in so many places, held together by a sea of faces”.

Which brings us to an inevitable question? Is this tour the full stop on Paul McCartney’s performing career and will December’s show at the Hydro mark his farewell to his Scottish fans? We’ve been here before, of course. Final show. Final encore. Final bow.

But this time feels like the end of a long and winding road, especially given the eight years that have elapsed since his last Scottish concert. Even for rock stars, the fat lady eventually has to have the final word. Yesterday really did come suddenly.

Paul McCartney plays the SSE Hydro in Glasgow on December 14