New testament scholars, both Jewish and Christian, have for years accepted the existence of a group of gentiles known as God-fearers. They were thought to be closely associated with the synagogue in the Book of Acts. Although they did not convert to Judaism, they were an integral part of the synagogue and provided fertile ground for early Christian missionary activity. As pious gentiles, the God-fearers stood somewhere between Greco-Roman piety and Jewish piety in the synagogue.
In his classic but now somewhat outdated study titled Judaism in the First Centuries of the Christian Era, Harvard scholar George Foot Moore argued that the existence of the God-fearers provides evidence for the synagogue’s own missionary work outside of Palestine during the first century A.D. The God-fearers were the result of this Jewish missionary movement. Although Jews may not have been actually sending out missionaries to proselytize the heathen, the influence of Jewish outreach was nevertheless felt in a world hungry for something more than mere empty religious forms.
Recent scholarship adds authority to Moore’s conclusions. The critical Greek words are phoboumenos (plural: phoboumenoi), meaning “fearing one,” and sebomenos (plural: sebomenoi), meaning “worshipping one.”