Fragments of St Thomas à Becket’s skull, the cloth used to wipe the sweat off Jesus’ face and the shredded remains of St Blaise’s foot are just some of many relics that inspired reverence and superstition in the medieval period.

Relics were the body parts of, or items associated with, saints or Christ.  Being able to own one or touch one was considered a priceless spiritual experience as people believed relics could heal illnesses, forgive sins and help them reach heaven. The “treasures of heaven” promised by the exhibition refer just as much to these grisly items as their gilded trappings currently on display at the British Museum.

Relics were housed in many ways but their containers, reliquaries, were nearly always made of precious materials or fashioned in a beautiful way. This exhibition has a whole range of reliquaries on display and what is staggering is the workmanship and money that has gone into them. Relics were housed in necklaces, gilded altars, ornate triptychs, and in intricately carved miniature ivory cathedrals. One relic was stored in a walrus tusk that also functioned as a throne leg.

The value and craftsmanship of these reliquaries highlights the level of devotion medieval Christians ascribed to the relics of Christ and the saints.  Their importance is summed up neatly by a phylactery (a reliquary designed to hang) of the Empress Helena, mother to Constantine. This golden object with delicately painted panels held a fragment of Christ’s cross in the centre and the four panels surrounding it detail the search Helena undertook to find the cross. One of the panels shows Judus Cyriacus revealing the cross’s location because he is being held over a fire.

One reliquary that stands out for its sumptuousness in the exhibition was the shrine of St Amandus. The saint’s remains were housed in a medium sized oak casket, carved to resemble a church with classical columns. The disciples are carved into the porticoes and the shrine is gilded in gold and inset with precious stones inset.

The most fascinating exhibits on display though were the “speaking reliquaries”.  These are shaped to represent the relics they held: they “speak” their contents. For example there was a slender silver arm-shaped reliquary on display that contained the arm of a child saint. The concept of reliquaries is, in general, somewhat disturbing because of the knowledge that these exquisitely-made items have macabre contents. Beneath the beautiful facade, body parts were rotting. However, the speaking reliquaries draw especial attention to their disembodied contents because of their shape. The idea that people would make pilgrimages to touch one of these rests uneasily.

In light of the double-edged nature of these objects, the exhibition’s curator deserves praise for the layout. The muted colour of the walls combined with the dim lighting that allowed the reliquaries to glisten, and the church music played in the background all contributed to the fitting impression visitors were entering a sumptuous tomb.

If you have a spare few hours in London this exhibition is well worth a visit for the amazing objects on display and the thought-provoking messages they have to offer.

“Treasures of heaven: saints, relics and devotion in medieval Europe” is exhibiting until 9 October at the British Museum.