Saint Hubert's Key

St. Hubert’s Key (Clef de Saint-Hubert, Hubertussleutel) is a sacramental in the form of a metal nail, cross, or cone. It was used in Europe until the early 20th century as a traditional cure for rabies and was named for St. Hubert, the patron saint of hunters, mathematicians, opticians and metalworkers.

Description
The key was heated and pressed to the area where a person had been bitten by a dog believed to have rabies. If performed soon after the bite had occurred, the heat had the potential to cauterize and sterilize the wound, eradicating the rabies virus. The practice was endorsed by the Catholic Church (the practice was seldom seen in Orthodox lands), and such keys were used by priests at places with which St. Hubert was associated, where the skin of humans and animals was branded as a protection against the bites of rabid dogs. This practice is recorded in the 1870s in the Ardennes region of France, where dogs were branded with St. Hubert's Key, as "a sure preventative of madness".

The memory of Saint Hubert's journey to Rome
The file led to the following hypothesis: having only appeared in Liège towards the middle of the 12th century, this historic relic could be part of the arsenal of supporting documents designed to restore the image of the Church of Liège, weakened by the Querelle des investitures. It wasn't until the middle of the 13th century that historical sources began to mention it, when the object underwent a number of transformations during the renovation of the building in which it was kept, the collegiate church of Saint-Pierre de Liège, the first burial place of Saint Hubert. The key is placed in the memory of Saint Hubert and his pilgrimage to Rome, which is an "anthropological necessity", the obligatory justification a posteriori for Saint Hubert's move to Rome and his direct contact with the relics of Saint Peter. The association of St. Peter with St. Hubert, of Peter with the founder of Liège, is an obligation for the foundation of a great Church: the association of the founder of the universal Church with the founder of the local Church.