St Isaac the Syrian: from Tehran to Moni Iviron, Mount Athos

This article examines recent discoveries and re-discoveries of the writings of Isaac of Nineveh (St Isaac the Syrian), focusing in particular on the recovery of previously unknown collections and the critical re-evaluation of the Greek textual tradition. Drawing on manuscript evidence and modern editions, it traces the transmission of Isaac’s works across linguistic and ecclesiastical boundaries, from their origins within the Church of the East to their reception in Greek, and subsequently in a wide range of other traditions. Special attention is given to the rediscovery of the so-called “Second Collection” in the Bodleian Library and to the emergence of a “Third Collection” from manuscript material in Tehran, as well as to questions of authorship and authenticity in relation to newly attributed texts. The article further highlights the significance of Marcel Pirard’s critical edition of the Greek translation, which provides, for the first time, a reliable textual basis for the study of Isaac’s corpus. It is argued that these developments do not merely expand the known body of Isaac’s writings, but fundamentally reshape our understanding of their transmission, textual formation, and reception. At the same time, they shed new light on the broader cultural and ecclesiastical dynamics through which Isaac’s works have acquired a remarkable ecumenical significance, culminating in their renewed recognition across multiple Christian traditions.