Today I learned that Devil's Advocate was actually a legitimate position in the Catholic church. Maybe this has been common knowledge for everyone for a long time (likely), but I never really pondered the origin of that term despite its prevalent use when discussing projects at work.
In the church, the advocates role was to argue against the canonisation of a saint; looking for evidence of fraudulent miracles and overblown claims of piety. Although the role no longer officially existed at the time, Christopher Hitchens was called on to speak against the canonisation of Mother Teresa in 2003.