It turns out a needle and thread have more medical applications than merely stitching up wounds. A recently rediscovered tapestry created by injured World War I soldiers is a gorgeous testament to the therapeutic powers of embroidery.

The five-panel grand altar tapestry depicting the Holy Grail, flanked by two palm leaves, was crafted by 133 wounded soldiers – blinded, crippled and shell-shocked – lying in hospitals around Britain, the Daily Mail reports. Medics hoped the project would distract them from their pain and help them recover.

The panels of the 3-meter-wide tapestry were pieced together by the Royal School of Art Needlework after the war ended and presented to St. Paul’s Cathedral, where the piece rested on the altar for several years. After the London cathedral was bombed during World War II, the altar tapestry was put in a chest for safekeeping and forgotten for more than 70 years.

In August, the tapestry will be displayed once again at St. Paul’s to acknowledge the 100th anniversary of the onset of World War I. It will remain on show for four years – the duration of the conflict. “It’s a symbol of faith despite everything and a deeply moving tribute to those who didn’t return,” says the Rev. Michael Hampel, of St. Paul’s, in a release from the cathedral.

The names of every soldier who worked on the project, originally recorded in a gold-leaf book, have been digitized and posted online, part of an effort by the cathedral to track down surviving descendants.