Hugh Etherianus (1110/1120-1182) was one of the principal theologians and polemicists who played a major role in the twelfth-century stage of the intensifying ecclesiastical and doctrinal tensions and disputes between the Byzantine Orthodox Church and the Papacy. His theological treatises and epistles have been an important and continued focus of the project “The Eleventh and Twelfth Centuries as Forerunners of a United and Divided Europe: Dialogues and Disputes between the Byzantine East and the Latin West,” funded by the Italian Ministry of University and Research since 2013. Pietro Podolak’s translation of Hugh Etherianus’s principal treatise De sancto et immortali Deo (1175-1177)into modern Italian (accompanied by translations of his four epistles which used to be transmitted with the tract, as well as an introduction and detailed comments) is the most recent of the valuable outcomes of this project. Within the framework of the project, in 2016 Pietro Podolak and Anna Zago published the editio princeps (and an Italian-language translation) of his earlier treatise, De minoritate ac aequalitate filii hominis ad Deum Patrem. In 2020 they also published a critical edition of De sancto et immortali Deo (along with the accompanying four letters, a contemporary commentary on the treatise, Compendiosa expositio, as well as the extant Greek fragments of the work). These editions and translations are making the theological and polemical legacy of Hugh Etherianus much more accessible to a wider scholarly and general audience.
De sancto et immortali Deo was dedicated to the evolving controversy over the filioque (the doctrine of the procession of the Holy Spirit from the Father and the Son which, in the early medieval period, had been included in Latin professions of faith and eventually was integrated in Latin liturgical practice). This dispute led to the convening of a doctrinal synod of Constantinople in 1166. The Byzantine Emperor, Manuel I Comnenus (1143-1180), played an active role in summoning the synod and its proceedings, as well as in commissioning Hugh Etherianus’s treatise (in view of his semi-official advisory position in the imperial court in Constantinople) in a symptomatic manifestation of the alignment and cross-influence across the Greek East and Latin West ecclesiastical divide. As could be expected, the provenance and development of the filioque controversy and Hugh Etherianus’s approaches to the dispute (explored in greater detail in Podolak's previous publications) are summarized expertly and to sufficient extent in the introduction (pp. 9-27). This part of the introduction also presents the contributions of recent Italian studies of this problematic text that are not always acknowledged and referenced in English-language scholarship. Given Hugh Etherianus’s proficiency in Greek and Latin and in the respective patristic and medieval texts, the remainder of the introduction deals both with text-critical issues and the Greek and Latin sources used and referenced in the tract: philosophical (classical Greek, Neoplatonic, and medieval Byzantine and Latin) and theological/exegetical (patristic and medieval). All these matters are addressed in greater depth and detail in the notes and commentaries to each of the three books of the tract, which further define and contextualize the main areas and courses of twelfth-century Byzantine-Latin exegetical and doctrinal debates and the related inter-textual dynamics inherent in Hugh Etherianus’s selection and articulation of philosophical and theological arguments, logical analysis, and dialectic (as conditioned by his earlier studies in Paris in the school of logic of Alberic of Mont Ste Geneviève). The detailed indexes of biblical and non-biblical passages and sources, places, and names further facilitate the main goals of the translation of the treatise, as articulated in the final sub-sections of the introduction.
Complementing earlier publications in the framework of the research project and recent studies such as Georgi Kapriev’s Lateinische Rivalen in Konstantinopel: Anselm von Havelberg und Hugo Eterianus (2018), the book carries forward scholarship and knowledge of the twelfth-century culture and climate of theological debate between the Byzantine Greek East and Latin West in the crucial area of the filioque, in which the dialogue format came to be used both in the Greek and Latin texts addressing the controversy. It highlights the twelfth century as an important stage in the longue-durée doctrinal and ecclesiastical rivalry between Rome and Constantinople and provides abundant evidence for why Hugh Etherianus’s tracts played such a significant role in the subsequent Latin polemical panoply against targeted Byzantine Greek theological and liturgical positions (early examples of which can be found in the Latin polemic against “Greek Errors”) in the decades following the inauguration of the Latin Patriarchate of Constantinople in the wake of the Fourth Crusade and the establishment of the Latin Empire of Constantinople in 1204.
With a detailed discussion of an extensive range of primary sources in the introduction and notes/comments, the book also clearly demonstrates that the study of the history and trajectories of the polemical struggles between the Byzantine Greek Church and Papacy, with its periods of widening divisions, schisms, overtures, and attempted rapprochements, needs to be firmly based on thorough and critical scrutiny of published and unpublished source material, especially in areas and periods which still remain insufficiently explored. Finally, the book redresses the balance of research in Byzantine-Latin inter-relations in the twelfth and thirteenth century, which understandably tend to be strongly focused mainly on the dramatic political and military developments which led to the Fourth Crusade and the fortunes of the Latin Empire of Constantinople, instead highlighting a richness of religio-political, theological, and cultural topics in the twelfth-century phase of these inter-relations that deserve much closer attention and further study.