How perennial sin is! The more history I read, the more it seems that there's hardly any evil in our modern world that the Church hasn't had to tackle many times already, in its past.
One of the most telling moments in C. S. Lewis' Narnia books comes in Prince Caspian, when a ghostly old woman hears the Narnians refer to the White Witch, who appeared to have been killed at the end of The Lion, the Witch, and the Wardrobe. She scoffs: "[W]ho ever heard of a witch that really died? You can always get them back."
And we do.