Spot-on
Nan, the expression "christian name" is a bit of a pythonesque anachronism :) It seems that this expression is still widely used in the UK. Another word derived from the religion of Christianity is "cretin". Cretin or Cretino (meaning "idiot") was originally used to describe a group on inbred coneheads living in the Alps. The idea is that even though they were disfigured and dim, they are still "Christians". Its surprising that the politically correct have yet not s-listed the word "cretin" as religiously offensive :P