In our age of relativism there is an urgent need for a comprehensive source book on authentic Catholic dogma that carries the full weight of the Magisterium of the Church while at the same time being both practical and easily accessible to clergy and laity alike - such a book is this English translation of Father Heinrich Denzinger's Enchiridion Symbolorum et Definitionum, or, as we more commonly know it Sources of Catholic Dogma, or simply Denzinger. Since it was first published a century and a half ago this handbook or collection (enchiridion) of articles (symbols) of faith and morals has enjoyed universal appeal and approbation since the pontificate of Blessed Pope Pius IX. The book has been updated periodically; this is the 1957 edition. The collection includes all articles and creeds of the Catholic Faith beginning with that of the twelve apostles all dogmatic definitions stamped with the Petrine authority of the Apostolic See (ex cathedra) decrees of the solemn Magisterium papal bulls, encyclicals and letters as well as some of the more weighty decisions of the Holy Office prior to 1957.