German Aquamanile in the Form of a Dragon, c. 1200, copper alloy, 8 3/8 x 4 3/8 x 7 3/16 in., The Cloisters Collection, The Metropolitan Museum of Art, New York, Photo via The Metropolitan Museum of Art.
An aquamanile is a vessel that holds water used for washing hands in both religious and secular contexts. Typically, the vessel is animal-shaped and has religious symbolism. During the Middle Ages, priests often used them to wash their hands before Mass.
This aquamanile is shaped like a dragon that is eating a man. Possibly it is a reminder of the perils of life.