A more thorough explanation:

Sacrilegus (sə-kril-ə-gəs) is an adjective and noun that comes from the Latin word "sacrilegious." In Roman law, it refers to a person who is guilty of sacrilegium, which is the theft of a sacred thing or the violation of an imperial law.

• If someone stole a religious artifact from a temple, they would be considered a sacrilegus.
• If someone disobeyed an order from the emperor, they could also be considered a sacrilegus.

These examples illustrate how sacrilegus is used to describe someone who has committed a serious offense against something that is considered sacred or important. In Roman times, these offenses were often punished severely, sometimes even with the death penalty.