I think the kind of christians he is refering to are those who are born in a country where christianity is the state relgion and you are automatically born as a christian like Finland etc. So there you will find many people who are regestered as christians but who are actually athiests or only visit the church when its for their own convenience or when there is some special function like christmas etc. Also these kinds of christians like to visit churches only on sunday to confess their sins because they feel guilty for all the shameful activities they have done during the past week.\n\nIn every religion you will find sincere followers and those who follow just for the sake of following. And because Christianity is the biggest world religion you find more of these kind of people. By percentage I cant say though...