Mustafa Mahmoud's book The Greatest Secret, in which he talks about many Sufi philosophical ideas

The Book of the Greatest Secret is a book written by Dr. Mostafa Mahmoud, in which he talks about many philosophical Sufi ideas, by quoting from poetic verses and writings written by the pioneers of this philosophical Sufism, such as Ibn Arabi, Abu Al-Azaim and other seniors of this school of thought.

The Book of the Greatest Secret is an enjoyable journey in the Sufi heritage, from which the reader learns rich information about many matters, such as union, solutions, manifestation, the theory of witnesses, exhausting spiritual exercises, asceticism, and other Sufi philosophical ideas and beliefs. The book is a journey into the depths of the Sufi heritage and mentions what it has and what it owes