2019 Reprint 1958 Edition. This book is based on a series of lectures and classes given on the meaning of the Revelation of St. John the Divine. In concludes that "There is but one truth, and all sacred writings are parts or fragments of the ancient wisdom which has come down to us from time immemorial. In the study of comparative religion and sacred writings we must come to the conclusion that a secret, traditional wisdom, an arcane science, underlies all these ancient writings." From the Introduction