Church keys A large number of forged keys in Sweden have three spheres on the bow and are therefore known as church keys. The same design is found on the door knockers of various medieval churches throughout the country. Keys are symbols of opening and closing, and opening the way to freedom. The key’s lock is mounted in the door, and together with the key, it symbolizes access to eternal glory in various cultures. In folklore, church keys had the power to cure the sick, tame unruly children, and catch one’s true love.