The Mysteries of Egypt and the Inner Meaning of the Riddle of the Sphinx constitute a concise study by Papus, which has been analyzed in parts over time in various works of his. The author, with his well-known vivid style, delves into the essence of the Great Mysteries of Egypt, namely, the tangible and specific evidence that a truly Initiated person received in order to realize the existence of their soul and spirit, and above all, to realize the existence of the divine world and divine beings.

Relying on ancient writers, archaeologists, and Egyptologists of his time, many of whom were Initiates, as well as on the works of great and well-known Esoterics - such as Fabre d'Olivet, Saint-Yves d'Alveydre, Éliphas Lévi, and others - he reveals the functioning of the Mysteries of Egypt in the invisible worlds, helping the reader to understand them through many tables and diagrams.