I mean the Westerners could deal with Athiest , more than other religions .You're shifting the goalposts again here. The irreligious are a minority at less than 1% in Greece. Regardless of whether there'd be a disinclination by the populace to elect individuals of certain religions, a law explicitly enshrining that discrimination is unjustified.
As for the Vatican - I don't think you know what the Vatican is, exactly. It isn't a country in the usual use of the term. It's a sovereign state only for the purposes of the impartiality of the Roman Catholic Church, so it isn't beholden to a particular government. It has no 'civilian' population. Almost all citizens are either members of clergy (i.e. priests, bishops, etc) or members of the Swiss Guard. Citizenship is granted only to those who are working in some specific role for the Vatican. It is rescinded when that role is over. The Vatican can't be fairly compared to countries in the normal use of the term.
I posted the exemple of Vatican to just understand my point , thanks for this new information about Vatican , that's very interesting !!
Do you want to say Vatican is country without population ?