They range from the finger of “doubting” St Thomas to the head of St Catherine of Siena, but holy relics must on no account be traded or sold, the Vatican has decreed.

The Holy See issued new guidelines for the preservation and display of saints’ relics, which once fueled a thriving trade in the Middle Ages, with bits of skin, hair, teeth and organs exchanged between abbeys and monasteries.

Websites and religious artefact shops offer saintly remains, sometimes of dubious provenance, for sale to devotees.

Ebay is full of such items, including an “antique brass case with the relics of three French missionaries killed in Vietnam” and an “ornate case with a relic of St Mary Magdalene dei Pazzi, an Italian nun.”