Since 1962 he taught for the Near East School of Theology in Beirut (since 1974 as professor for New Testament studies), where he founded the Institute for Middle Eastern New Testament Studies.
Seit 1962 lehrte er an der Near East School of Theology in Beirut (seit 1974 als Professor für Neues Testament und Vorsitzender am Biblischen Institut), wo er das Institute for Middle Eastern New Testament Studies gründete.