The so-called Risālat Al-Ḥurūf (epistle on letters) ascribed to Sahl Al-Tustarī and letter mysticism in Al-Andalus

Abstract Our paper reconsiders the ascription of an unnamed epistle on letters to Sahl al-Tustari, a distinguished {S combining dot below}ufi master from Ba{s combining dot below}ra (283/896). This short epistle is part of a unicum manuscript: Chester Beatty no. 3168, a codex comprising of various manuals and treatises on letters, divine names, invocations, esoteric practices and similar topics. It was found by M. K. I. Jäfar, who, although this epistle appears in the manuscript with no title and no explicit author, attributed it to Sahl al-Tustari and named it Risalat al-{h combininig dot below}uruf (Epistle on Letters).Under this title and authorship the text was published twice: first by Jäfar and later by Pillar Garrido. The paper consists of an introduction, translation and a detailed commentary of the epistle. In addition to reviewing the question of authorship, our paper wishes to examine the mystical philosophy which this epistle, as well as other sources, exhibit; in particular the mystical-philosophical vision of letters as the building blocks of creation in a hierarchical cosmological and cosmogonic process. Working from a comparative and historical approach, we came to the conclusion that this epistle could not have been composed by Sahl al-Tustari. Although we could not offer an identification of authorship, we could place the epistle within an intellectual milieu in which 'letter mysticism' occupied an important position, especially from an occult-theosophical approach. We could find parallels of such an approach in Shïi-Ismäili literature as well as in the works of Andalusian mystics, in particular the tenth-century Ibn Masarra in his Kitab khawa{s combining dot below}{s combining dot below} al-{h combininig dot below}uruf (Book on the Properties of Letters - also included in the same codex), and the twelfth-thirteenth-century Ibn al-Ärabi.