LONDON.- Could there be a more powerful and enduring expression of devotion than depictions of Christ and the cross? There are certainly no other religious images that have been made in so many locations over so many centuries.

Starting on Ash Wednesday, the exhibition ‘Cross the World: Building Bridges in Wood’ will be at Westminster Cathedral, London. It is a rare attempt to bring together the global diversity of crucifixes and other types of cross in one place, side by side.

Also bringing the world together is the raw material of the exhibits. Wood exists in every inhabited part of the world, forming both a gloriously tactile item of home decor and the brutal fabric to facilitate a crucifixion. It is appropriate that this exhibition of wooden crosses should be in the Cathedral’s Chapel of St Joseph, whose feast day is in Lent. The foster father of Jesus was not only a carpenter and a model of selflessness; he was also a refugee parent looking after a wife and child during their flight into Egypt.

There are crosses from all corners of the planet. In addition to the better-known locations, such as Europe and Latin America, there are examples from Africa and Asia — the fastest-growing Christian communities in the world. China, in particular, provides an unexpected array of crosses inlaid with mother-of-pearl from the 19th century. The Holy Land was formerly a highly creative producer of crosses but is less so these days. Even less are the neighbouring lands of Syria and Iraq. The exhibition features one crucifix brought to the exhibition by the Chaldean Catholic community of Iraq; it is the only example to have avoided destruction by ISIS in the Nineveh Plains town from which it came.

As 2017 is likely to be the Year of the Barrier, this exhibition provides an opportunity for art enthusiasts to see the interconnectedness of a world that has been globalised for centuries. It’s a reminder that the same type of people who in the past tried to stop trade and communication by persecution of selected faiths are still alive today. They are busy building walls and not much else. The title of the exhibition refers to a comment make by Pope Francis last year on the subject of politicians who prefer to build walls instead of bridges.

Regardless of political and religious convictions, the cross is a potent and often beautiful symbol for humanity. The thought of a fellow human going through the torment of crucifixion should give everyone cause for reflection. It happened in Roman times and it’s still happening now.

‘Cross the World: Building Bridges in Wood’, from March 1 to 28 at Westminster Cathedral, London, UK. The exhibition is by the Museum of the Cross, a museum that will open in 2018 in Lorraine, France. Entry to the exhibition is free.