A hardcover book first published by Barry and Rockliff in 1962, this second revised impression was published by Servire BV, of Katwijk, Nederlands in 1979 for the International Headquarters of the Sufi Movement in Geneve, Suisse. These collected essays by Hasrat Inayat Khan were printed in the English language by the Delta Lithograh Company of Van Nuys, California. There is a black and white photograph of the longhaired and bearded author facing the title page.

A short Preface in the 278 page book explains that 'the present edition of this book, which consists of a collection of lectures delivered by Hazrat Inayat Khan during the years 1918-1920, is the fifth, the first having appeared in 1921...eleven hitherto unpublished lectures have been added to the 29 which were included in the earlier editions.'