Trying to find a rather silly short story, or the collection it was in:
A pair of priests come to a village, where a female pig is apparently possessed by the devil. The sow committed a number of heinous acts, including eating her own piglets, and when they confront the sow, she chases them up a tree.
However, by dangling a cross on a cord from the tree they succeed in exorcising her, and she becomes the most virtuous and pure pig ever known. She apparently also performs some miracles and is later elevated to sainthood, thought the story does not go into many details.
This was in a collection of short fantasy stories by different authors, I think the title of the collection was "Fantastic Stories" or something similar, and the cover was purple-ish or blue without any images. I believe I read it 20 years ago, in a library, in German.
The book contained another story, about a boy going into the woods to drink from a creek, whereupon a strange poem about a "communion" resounds in the air.
I would be happy to find either of these stories, ideally the whole collection this was contained in.