It wasn’t a long journey, really, from East Jerusalem to Bethlehem in the central West Bank, but it went across ancient borders and boundaries and checkpoints. We were on our way, a group of five from the non-profit global exchange group Narrative 4, to the Aida refugee camp in the shadow of what the Israelis call the “separation barrier” and the Palestinians call the “apartheid wall”. Among our group was Colm Mac Con Iomaire, an Irish fiddle player, one of the finest musicians in the world.

We abandoned the taxi at Checkpoint 300 and left Colm’s fiddle in the car, knowing that we were quicker on foot, but that the taxi would bring the fiddle along later: everywhere we went in Israel and Palestine, Colm would open up the eyelids of the day by playing a tune.

‘We shape a better future despite everything we come up against’ … Abdelfattah Abusrour, founder of the community arts organisation Alrowwad

We were met by Dr Abdelfattah Abusrour, founder of Alrowwad, a community-based organisation for the arts in the heart of the camp. We were there to talk about a possible collaboration between the young people in his camp and schools all over the world: Limerick, Birmingham, Chicago, Newtown, Port Elizabeth, Tampico.

“We left our music in the taxi,” Colm apologised.

“Oh, you’re a fiddle player,” said Abdelfattah, off-handedly, pointing to a corner where a small pile of rubber bullets, gas cannisters and “sound bomb” shells also sat. “We were just given a fiddle by a lady in England, but it’s broken and nobody knows how to fix it.” And in the cramped office space, Abdelfattah began to talk of his concepts of beautiful resistance, using stories and music and dance and theatre to allow young people and women in the camp to become changemakers.

Colm rose noiselessly from his chair and reached for the modern-looking case. The violin looked like something long ago sound-bombed. The strings were twisted. The bridge was hanging off.

Upon the possibility of hope one always tastes the possibility of sorrow: the violin looked like my cliched concept of a refugee, silent, unstrung.

Colm began to work with the strings. “Art puts us on an equal ground,” said Abdelfattah. Colm turned the bridge around. “We shape a better future despite everything we come up against,” said Abdelfattah. Colm loosened and tightened the pegs, adjusted the chin rest. “We do not want your sympathy,” said Abdelfattah. Colm made the strings taut: the violin began to look half-musical. “Seventy per cent of those who go through the Alrowwad programme don’t go to prison,” said Abdelfattah. Colm positioned the tail-piece. “People think these kids know only how to throw stones,” said Abdelfattah, “but we write, we sing, we dance, too.”

The violin looked half sober. Colm worked his fingers around the peg box, plucked the strings, tightened and untightened the pegs, tuning from low to high. There were two bows in the case. One was brand new, unrosined. The second was older. Colm took a hold of the second one. The room waited. We had no idea if it would make any sound.

This is the music of what happens: a plume of dust rose from the violin. It seemed to me a moment so theatrical it could only be true. Later, I learned that it was rosin dust rising from the bow hairs, but at the time it seemed that the thing was emerging from another age.

Colm played Róisín Dubh, an Irish love tune from the 17th century. No singing, no words. The sound of the violin made a brand new lung of the room. He followed it with an improvised fusion piece involving the call to prayer, a dance tune we had learned in Nablus, and rap rhythms heard in Israel. It was some of the most glorious music I have ever heard.

And then Abdelfattah – who had visited Belfast – asked if he knew the song Only Our Rivers Run Free. Again, no singing, but the words were there: “Where are you now when we need you?”

The morning pressed up against us. We had to leave. But our stories never necessarily end. Colm found a tag in the case – from a shop in Bristol, England. He figured the violin was probably late 19th-century, maybe early 20th. An unopened envelope from the donor read: “To the New Owner of this Violin.”

The letter remained unopened. The fiddle would now be passed to a young person in the camp.

We found our taxi. Colm’s original fiddle was sitting on the back seat. It, too, was an ancient piece: it sat there, speaking to us.

• Apeirogon by Colum McCann is published by Bloomsbury on 25 February (£18.99). To order a copy go to guardianbookshop.com. Free UK p&p over £15.