Of all the reminders of the worst of human behaviour, the crucifix is surely the most potent. It symbolises something everyone, in every society, can understand: the slow, torturous death of one individual at the hands of others.

But what is fascinating is how, across 2,000 years, artists have translated this slow and degrading form of execution into beautiful objects of devotion; in fact the image of the crucified Christ is quite probably the most powerful and enduring symbol the world has ever known. That’s certainly what has inspired me over the past 20 years, as I’ve assembled a collection of crucifixes that bring together a wide range of responses, from different cultures across the planet, to that seismic event that took place in Jerusalem so many centuries ago.

My hope is that the collection will eventually be housed in a museum in Lorraine, northeastern France. Before this happens, selected objects from the embryonic Museum of the Cross are being displayed in an exhibition at Westminster Cathedral. The unifying medium of the exhibits is wood; it is a material that exists in every inhabited part of the planet, forming both gloriously tactile objects and the brutal and entirely appropriate fabric of a cross.

The aesthetic appeal of the crucifix is a paradox. I was once asked whether an icon of the electric chair could have been developed in the same way; the answer is no. A crucifix is more than just an artistically composed instrument of execution. The materials used to depict it are essential. The crucifix allows for a multitude of forms far exceeding the possibilities of an electric chair or an axe. Wood, above all, is the building block of the most expressive depictions of the condemned individual’s final hours.