It seems to me that the reason why so many people have trouble accepting that Roman Catholicism is not a true Christian denomination is because Catholicism does not deny the fundamentals of the Christian faith so much as add to them. An example of this is the Alpha Course. Roman Catholics have their own version of this which is the same as the Protestant version but with the addition of two extra chapters dealing with Roman Catholic sacraments and other practices of the Roman church.
Why is adding to the Christian faith a problem? Surely as long as we all agree on the fundamentals that is enough? For an answer to this, first read the book of Galatians. Then listen to the video on this link here.
