“I will pay thee as soon as the oak leaves fall; come then, thy money will then be ready counted out.” When the oak-leaves had fallen, the Devil came and demanded what was due to him. But the Lord said, “In the church of Constantinople stands a tall oak-tree which still has all its leaves.” With raging and curses, the Devil departed, and went to seek the oak, wandered in the wilderness for six months before he found it, and when he returned, all the oaks had in the meantime covered themselves again with green leaves. Then he had to forfeit his indemnity, and in his rage he put out the eyes of all the remaining goats, and put his own in instead.

This is why all goats have devil’s eyes, and their tails bitten off, and why he likes to assume their shape.