Beliefs and practices
Common features in Roman imperial times
For the first three centuries of the Christian Era, the different mystery religions existed side-by-side in the Roman Empire. They had all developed out of local and national cults and later became cosmopolitan and international. The mystery religions would never have developed and expanded as they did, however, without the new social conditions brought about by the unification of the Mediterranean world by the Romans. In the large cities and seaports, men from the remotest parts of the empire flocked together. Many people were removed from their accustomed surroundings and suffered from loneliness. They longed for new acquaintances and for assimilation, and they needed the assurance that only the knowledge of belonging to a community can give. Economic and political conditions in the Roman Empire also accelerated the growth of the mysteries. Members of a mystery society helped one another. For a lawyer, a craftsman, or a contractor, membership in a club could be the road to success. Furthermore, there is less opportunity for private initiative in a society ruled by a monarch than in a democratic society. The individual who felt that his initiative was frustrated by the preponderance of the imperial structure might well turn to a community that offered him the hope of a better future. The mystery societies, thus, commonly satisfied both a taste for individualism and a longing for brotherhood. At least in principle, the members of the communities were considered equal: one man was the other man’s brother, irrespective of his origin, social rank, or nationality.
Because membership in each of the mystery communities was a matter of personal choice, propaganda and missionary work were inevitable. In the religions of Isis and Mithra, missionary zeal was particularly obvious. The followers of Isis and Mithra considered Rome to be the centre of their worship, and the city was called sacrosancta civitas (“sacred city”) in an Isis romance written in the 2nd century ad by the Latin author Apuleius.