"Near the end of a millenium satan shall return and walk amongst us not as beast but as beauty." - the Etruscan Book of the Dead.
THis I have no idea. the Etruscan religion is a bit confusing, and hard to track as a lot of the information I have found compares it to Egyptian religious beliefs so I would guesss that the passage you asked about might just be fictionalised to add effect to the film. I am probably worng, but hopefully this is a start.