Syriac scholar and monk of the Benedictine Abbey of Metten (Germany). At Munich University he studied Arabic, Hebrew, Syriac, and Coptic, as well as Greek and Latin, and subsequently he taught oriental languages at the Collegio San Anselmo, in Rome (1939–61, 1967–8). His first work on Ephrem was a monograph on the ‘Hymns on Faith’ (1949); this was to be followed by six further monographs (listed below) and many articles on different aspects of Ephrem’s writings; above all, however, he is primarily known for his editions of Ephrem’s poetical works in the CSCO, produced between 1955 and 1979 (a total of 19 pairs of volumes; see under Ephrem).