Catholicism and Fundamentalism What is in this book that has led so many Protestants to convert to Catholicism? What truths are revealed that has caused so many lapsed Catholics to return home? Find out for yourself when you read Catholicism and Fundamentalism by author and Catholic Answers’ founder Karl Keating.
"The gravest obligation requires the acceptance and practice, not of the religion which one may choose, but of that which God prescribes and which is known by certain and indubitable marks to be the only true one."
~ Leo XIII in his Encyclical Immortale Dei (November 1, 1885); on our fundamenal duty; (from the article Religious Toleration)