Since Protestants can be saved and it is ever so much easier to be a Protestant, where is the advantage in being a Catholic?
Firstly, remember the conditions of salvation for a Protestant. If he has never suspected his obligation to join the Catholic Church, it is possible for him to be saved. But it is necessary to become a Catholic or be lost if one has the claims of the Catholic Church sufficiently put before him. I myself could not attain salvation did I leave the Catholic Church, unless, of course, I repented sincerely of so sinful a step before I died. Secondly, it is easier to live up to Protestant requirements than to live up to Catholic requirements. Non-Catholic Churches do not exact so high a standard of their followers as does the Catholic Church of hers. But that is not the question. It is much easier to be a really good Christian in the full sense of the word as a Catholic than as a Protestant, and surely that is what we wish. What advantages contribute to this? They are really too many to enumerate in a brief reply. The Catholic is a member of the one true Church established by Christ. He has the glorious certainty of the true Faith, and complete knowledge of the whole of Christian truth is much better than partial information, if not erroneous information. By submission to the authority of Christ in His Church he has the advantage of doing God’s will just as God desires. If he fails at times by sin, he has the certainty of forgiveness by sacramental absolution in the Confessional. He has the privilege of attending Holy Mass Sunday after Sunday, and the immense help of Holy Communion by which he may receive Our Lord Himself as the very food of his soul. He has the privilege of sharing in the sufferings of Christ, by observing the precepts of fasting and mortification. He receives innumerable graces from Sacramentals and from the special blessings of the Church. He may gain very useful indulgences, cancelling much of the expiation of his sins which would otherwise have to be endured in Purgatory. And he is more loved by God in virtue of his being a Catholic even as God loves the Catholic Church more than any other institution on the face of the earth. In short, even as there is an advantage in being a Christian rather than a pagan, so there is an immense advantage in being a true Christian and belonging to the one true Church rather than to some false form of Christianity. Thus a good Catholic has many advantages over and above those possessed by a good and sincere Protestant. But, as I have remarked, if a Protestant begins to suspect his own Church to be defective, inquires into the matter, and becomes convinced that the Catholic Church is the true Church, he has no option but to join that Church if he desires to avoid the risk of eternal loss.
Outside the Church no salvation, Question 547 from Radio Replies Volume I Copyright © 1938 (by Rev. Dr. Leslie Rumble, M.S.C. and Rev. Charles Mortimer Carty).