In Poland, in the parish church of Schwarzenstein, hang two horse-shoes: the legacy of an interesting tale.
In the village of Eichmedian, a mile from Rastenburg, there lived a woman who was a tavern-keeper. A greedy woman, she charged double to honest rate for board and lodging. Late one evening, a group of guests accused her of cheating them. Defending herself, she swore an oath before them, saying,
Then ride my back the Devil must!
To her horror and the amazement of all present, the room suddenly darkened and the Devil suddenly appeared before her. He gestured, and unable to resist, she knelt on all fours. She felt herself growing and changing, and the Devil mounted her back as she tossed her head and made whinnying sounds. In seconds she stood before the dumbstruck guests as a bay mare, and the Devil gave a great laugh and rode her out of the building and out of the village.
At headlong speed he rode her to the town of Schwarzenstein, and to a blacksmith's shop there, arriving in the small hours of the morning. He roused the blacksmith and demanded that his steed be shod at once. The blacksmith, yawning, complained of the late hour and that his forge was shut down and cold. But the Devil insisted and promised gold if it were done swiftly, and so the blacksmith agreed. He lit his furnace, and had the Devil work the bellows. The blacksmith had not long begun his work however when the mare began to speak, evidently having worked out how to form human words with her equine lips. "Don't you know me?" she begged. "It is I, the tavern-keeper of Eichmedian!"
The blacksmith was horrified and nothing could persuade him to continue with the shoeing. The Devil raged but there was nothing he could do, and as a cock heralded the arrival of dawn, the spell was broken. The Devil vanished and the tavern-keeper returned to her human form. Repenting of her greedy ways, she had the two horse-shoes which the smith had already fashioned nailed up in the church as a warning to other cheats.