The first editions of 1927, 1928 and 1933 were of limited publication. The fourth and most complete expansion of the text by Paul Case was finished in 1937, revised by him in 1953 just before his death, and published in hardcover by Weiser in 1985. It represents the full maturity of his thought on this subject.
[Case] . . . develops a profound analysis of both the pre- and post-Masonic Rosicrucians and sheds some wonderful light on Freemasonry to boot! [Case] defines Rosicrucianism very simply as Christian Hermeticism allied with Kabbalah. His elucidation from this simple clear viewpoint is one of the clearest and most helpful yet produced for those actually on the path. -Gnosis Magazine
Case was considered an authority on Western mysticism. His “Rosicrucian order” is not an organization but the medieval tradition itself. His explanation of the classical Rosicrucian grades vividly lays out ascending principles-truths expressed differently, according to individual readiness. -Brain/Mind Bulletin