A White Night - Julia Parzyck

I had a very hard time following this story and still not sure if I get the gist of it yet. I took it as some travelers came upon a church and ended up watching a sacrifice of a woman who committed a crime and is put to the death. I still am not sure what the crime was, adultery? I am not sure which is why I am mostly confused. What also confused me was why the bystanders did nothing to stop them, is it because she didn't make much sound? I just felt that if I came upon something like that I would have to stop them but I guess maybe it was because they weren't supposed to be there. Also someone else mentioned in a post about her wearing white which I thought was very interesting. It didn't come to mind that wearing white often comes off as being "pure" which is the women committed adultery then she wouldn't be pure. I am not sure, I am utterly confused.