The original edition on the basis of which this book was released was distributed in Milan in the form of three brochures within the youth movement, which was then called "Student Youth." These brochures were called: Reflections on One Experience (1959), The Path of Christian Experience (1960), Notes on the Christian Method (1964). We offer the most substantial parts of this original edition, revised, recomposed and edited by the author, in the belief that even today they represent an unusually valuable stimulus for thinking about the enduring significance of Christianity as an event.