The Ikhwān al-Ṣafāʾ (Brethren of Purity), the anonymous adepts of a tenth-century esoteric fraternity based in Basra and Baghdad, hold an eminent position in the history of science and philosophy in Islam due to the wide reception and assimilation of their monumental encyclopaedia, the Rasāʾil Ikhwān al-Ṣafāʾ (Epistles of the Brethren of Purity). This compendium contains fifty-two epistles offering synoptic accounts of the classical sciences and philosophies of the age; divided into four classificatory parts, it treats themes in mathematics, logic, natural philosophy, psychology, metaphysics, and theology, in addition to didactic fables.

Epistle 52a consists of the shorter of two versions circulating as the final epistle of the corpus, ‘On Magic’. In this version, the authors regard magic and other occult sciences as the culmination of their own philosophical teaching, and they justify the ‘rightful use’ of these disciplines, especially astral magic, with reference to great authorities of the past, such as works of Plato and Abū Maʿshar, the Quʾran, or even Jewish stories allegedly from the Torah. Most interestingly, the text occasions an extended account, unparalleled in Islamic literature in its sympathetic approach, of the mysterious Ṣābiʾans of Ḥarrān. The present edition is accompanied by comprehensive footnotes and a substantial introduction, which argues for the authenticity of this treatise and offers a glimpse of the significant impact it exerted on later works in this field such as the Ghāyat al-Ḥakīm (Picatrix).