Gerard Morrissey is the pen name of a priest who has been active for more than forty years in promoting devotion to the Blessed Mother. In this work he offers concise, easy to understand explanations of the role and authority of the Pope, the Magisterium and the theologian. He describes the development of doctrine, how some Church teachings can be changed and others cannot and the reasons why they cannot be changed. The book is a short apologetics course for the Catholic who wants to understand his or her faith better.