The strange myth in the song Jerusalem

The Holy Thorn in Glastonbury

England may soon have its own national anthem and the odds-on favourite is Jerusalem. The famous song has a rather strange myth at its heart, writes Gareth Rubin.

Jerusalem is the musical setting of William Blake's poem Prelude to Milton. But Blake, a Romantic whose poetry and paintings often tended towards the bonkers end of "visionary", wasn't merely musing on the holy influence in England. He was specifically thinking about a legend that as a boy, Jesus of Nazareth visited England with his great uncle, Joseph of Arimathea, who was a sailor and trader. The "feet" in the line "And did those feet in ancient time" refers to Jesus.

Some try to justify the legend on the grounds that Joseph might have come to buy tin from Cornish mines, but if there is any hard evidence at all, it has yet to come to light.

Instead, the legend of Jesus walking upon England's mountains green is part and parcel of the cycle of medieval legends about Britain's own King Arthur. Those stories say that after Jesus's Crucifixion, Joseph took the Holy Grail to Glastonbury, where he established the first English church. But that's not all he left. According to the 14th Century monk John of Glastonbury, Arthur, the greatest of British heroes, was Joseph's great-great-great-great grandson - and therefore related to Jesus himself.

One of the most famous legends about Joseph's time in Glastonbury states that one night he struck his staff into the ground and went to sleep. When he awoke he saw that a hawthorn tree had miraculously sprung from the staff - and the Holy Thorn survived until it was cut down as a relic of superstition by the puritanical Roundheads during the Civil War. It was replaced by the local council - twice - in the 1950s, only to be hacked down with a chainsaw six years ago. No one is really sure why.

So why did Blake spin a poem about a medieval myth? Probably because England at the time was a place of change and he wasn't entirely happy about the direction it was taking. It was the time of the Industrial Revolution, when factories - the dark Satanic Mills he wrote of - seemed to swallow people up and spit them out broken and mangled. As a nonconformist Christian, Blake looked back on a time when a religious figure could walk in barefoot simplicity on "England's green and pleasant land".

And Blake isn't the only one to turn to the legend when writing about England in bloom. Irish rocker Van Morrison's song Summertime in England includes the line: "Did you ever hear about Jesus walkin' / Jesus walkin' down by Avalon? [Glastonbury]."

Sadly for those who want to draw a direct connection between the West Country and the Son of God, Diarmaid MacCulloch, professor of church history at the University of Oxford, describes the legend as "totally implausible". "It obviously didn't happen. Why should a carpenter's son from the eastern Mediterranean even think of coming here. It's just silly English self-promotion. Nothing more to it than that."

Still, it's not a dead loss, suggests MacCulloch: "Blake was a mystic, and he was saying, in his lovely poetry, that God dwells everywhere - including England."

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