This article is 52pp., so prepare thyself.  I do not know how this priest died, but he makes many worthy distinctions in this article.  I will not summarize the article, as it is there for anyone to read.  I will say that it is abundantly clear to the author and to us that two things are necessary in light of Pius XII's Mystici Corporis - that Church membership entails two requisites, 1. water baptism 2. mental faith. 

It is clear by the author's tone at the very end of the article that he was not a fan of Pope John XXIII.  The author wrote a book on the sacraments in 1967, but I have not read it.  Article is from The Thomist: vol. 27, 1963.