After a distinction between private religious visions and prophetic religious manifestations this book provides a deteiled description of the great Marian Apparitions in Guadalupe, La Salette, Lourdes, Fatima, Medjugorje and Kibeho. These events are investigated with the axiomatic method, describing its essential features with axioms and definitions from which theorems are derived. The axioms and theorems consider the events to be miracles; they cover the credibility of the events, the reliability of the seers, the voluntary component of the believers and the content and seriousness of the messages given to the people in the whole world. In addition a comparison is made between the prophetic apparitions of Mary and Christian Revelation. This book defends that the ultimate origin of the prophetic manifestations of Mary, including her messages to the world, is God. ¿Ein innovativer Zugang zum Phänomen Medjugorje¿ Cardinal Schönborn, Wien