Although it has long been regarded as one of the greatest records of all time, interviewers who have, over the decades, ventured to broach the topic of Astral Weeks with Van Morrison have often met with a rather frosty response.

It may, according to no less a fan than Elvis Costello, rank as “the most adventurous album made in the rock medium” but Morrison says Warner Brothers barely promoted it at the time, with the result that sales left him hardly enough money to pay the bills.

One suspects that Morrison’s reluctance to glory in his febrile jazz-folk masterpiece, which he recorded at the age of just 22, may also stem from the serendipitous circumstances that produced it. Two sessions recorded with American musicians, barely known to him at the time, established an artistic high water mark that, in recent years especially, Morrison has struggled to match.

It would be naïve to think that the volte-face represented by this beginning-to-end recital of the album was undertaken in a spirit of smiling rapprochement. In Morrison’s world, for a start, little is done smilingly, and besides, the posters in the foyer advertising a new album on his own imprint Astral Weeks — Live (recorded last year at the Hollywood Bowl) underscored that this was good business.

Whatever Morrison’s motives, however, the singer’s famously exacting levels of perfectionism meant this was a task undertaken anything but lightly. The fact that the 64-year-old singer had gone to the trouble of locating guitarist Jay Berliner — sometime sideman to Charles Mingus and present on the original Astral Weeks sessions — suggested as much. A vital presence here, the New Yorker hunched over his guitar and embroidered his way around the iconic tap of the song’s title track with an arresting fluency that obliterated the intervening years.

Inevitably though, it was hard to avert your gaze from a surprisingly trim-looking Morrison, who seems set on revealing surprisingly little of himself these days. As a result, the ever-present shades and hat seemed to accentuate the incongruously orange sheen of his hair.

After the death of James Brown, it’s hard to think of another band leader who elicits such deference from the musicians around him. Initiated via a repertoire of bewilderingly complex hand signals, songs long since etched in the memory of fans revealed magnificent new depths. The love-drunk rapture of Sweet Thing and The Way Young Lovers Do burst to life with new colour amid the ornate soloing of violinist Tony Fitzgibbons. Locked into each other with almost telepathic empathy, rhythm section Robbie Ruggiero and David Hayes lent a purposeful, celebratory zip to an extended Ballerina.

The longer Morrison mapped out the verdant, mystical postwar Belfast so vividly depicted in songs like Cyprus Avenue and Madame George, the more fascinating it became to watch the behaviour they inspired in their creator.

In the one-hour “warm-up” of old hits that preceded this set, Morrison had remained relatively aloof from his band, even when turning in soaring reconfigurations of It’s All in the Game and Caravan. In keeping with the semi-improvisational nature of the Astral Weeks songs, however, Morrison’s body language was gradually transformed. The hand-signals may have persisted, but increasingly, Morrison the band leader seemed no less happy to be led by the joyful noise that surrounded him.

Encircled by his own musicians, in thrall to the jazz-folk sub-genre singlehandedly invented and, many would say, never bettered by these songs, two eyebrows rose plaintively above Morrison’s shades. “I believe I’ve transcended,” he averred.

If the five-minute ovation encompassing all of a seismic, valedictory Gloria was anything to go by, he wasn’t the only one who thought so.

Colston Hall, Bristol, June 20; Wales Millennium Centre, Cardiff, June 21

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