The Epistles of the Sincere Brethren

The Epistles of the Sincere Brethren, known in Arabic as Rasāʾil ikhwān aṣ-ṣafāʾ wa khillān al-wafāʾ, is an encyclopedic work produced by a secret Arab confraternity in Basra, Iraq, likely in the latter half of the 10th century AD. The group, called the Brethren of Purity, reflected the doctrines of the Ismāʿīlī Muslim sect, which was influenced by Manichaeism and Neoplatonism.1

The Brethren of Purity sought to integrate Greek philosophy with their own beliefs, adopting an orthodox Neoplatonic stance. They incorporated Hermetic, Gnostic, astrological, and occult sciences, believing that by absorbing ancient wisdom, they could understand the esoteric meaning of revelation. Their philosophy posits that individual human souls emanate from and will eventually rejoin a universal soul, which itself will unite with God on the Last Judgment. The Rasāʾil are structured to guide the soul from concrete to abstract knowledge, aiming to purify it of misconceptions and lead it to a clear understanding of reality, thereby ensuring happiness in the afterlife.1