For many people in "Catholic" countries like Spain, France, Italy and SOuth America, the Church is a cultural institution as much as a religious one. If anything it is more cultural, and
the Church of Rome is in a real battle in Latin America right now for "religious" supremacy over up and coming evangelical churches.

I raise this because it would be nothing for someone like Clemenza or Luca to bless himself if he passed a church on the way to do a hit, just as Vito who coldly tells Tom his dead son was a bad don, but still manages a "rest in peace" comment in there.

Michael was a great deal more cynical and I doubt he paid more than lip service to the church (until GF III when he paid $100 million to get into that Society).