The Author of the Book in a Few Lines

According to what is stated in the first volume (pages 256 to 268) of the book The History of the Shia Extremists (Tārīkh Ghulāt al-Shī‘a) by the great author Shaykh Hussein Harfush, the author of the Egyptian Epistle is Prince Muḥammad, titled ‘Iṣmat al-Dawla.

He is Prince Muḥammad Abū al-Fatḥ, titled ‘Iṣmat al-Dawla, son of Prince Mu‘izz al-Dawla ‘Alī ibn ‘Īsā Kawbaj—may Allah be pleased with him. He was born in the year 391 AH.

As appears from the text of his own epistle, he says:

"Abū al-Fatḥ al-Baghdādī opened [this knowledge] unto me on the tenth day of Muḥarram in the year 407 AH. Allah's favor was flowing upon me through him. This took place at the house of my father, Mu‘izz al-Dawla, in Cairo, when I was sixteen years old."

Thus, his birth date is established as mentioned. He was chronicled by his contemporary, Shaykh Abū Ṣubḥ al-Daylamī, who praised him and his father. He was also cited by Abū al-Khayr Salāma ibn Aḥmad, known as al-Ḥaddād, in his own epistle among those who met him.

Abū Ṣubḥ al-Daylamī stated:

"The noble, esteemed, and well-born Prince Abū al-Fatḥ, titled ‘Iṣmat al-Dawla, was a man of worship, asceticism, and piety. He authored many works on Tawḥīd (Divine Unity), the most important being the epistle known as The Path of Knowledge and Clarification and the Delight of Hearing and Vision. It is famous among us on the Coast and in the Mountains as The Egyptian (al-Miṣriyya), and is also known as The ‘Iṣmiyya. His father was Prince Mu‘izz al-Dawla."

He continued his praise at length, adding:

"He composed poems and fragments on Tawḥīd. His teacher in the doctrine was Abū al-Fatḥ Muḥammad ibn al-Ḥasan ibn Muqātil al-Baghdādī, who himself has fragments and compositions on the esoteric (al-Bāṭin)."