During the first six hundred years of the Christian Church's existence many changes occurred. Of these the most dramatic and remarkable was the shift from being a persecuted sect which, in order to fulfil its destiny as a universal faith not tied to a particular race, had to sever the umbilical cord to Judaism, and so to capture society and the Roman empire. From embodying a counter-culture to being seen as a mainly (not invariably) conservative social force was an extraordinary step. The number of martyrs did not need to be very large for their 'witness' to be public and 'newsworthy'. Remarkably soon the Church had recruits in high society, and as early as the middle of the second century was dreaming of a day when the emperor himself would be converted. The Christians changed the dominant form of religion in the Roman empire and thereby imprinted the most important difference between ancient and medieval society.
Not that the Christians had a wholly different culture from that of 'antiquity'. They came out of a society which to educated Greeks and Romans could be labelled 'barbarian'. Defenders of Christianity devoted pages to arguing for the superiority of barbarian ethics and religious ideas. By the late third and fourth centuries the Christians were supporters of the good order and law of the Roman empire. In his commentary on Paul's epistle to the Romans Origen could say that the task of magistrates was to restrain overt and public delinquencies, whereas sins (which could be highly anti-social) had to be corrected by bishops with ecclesiastical discipline. The latter, of course, were successful only with church members acknowledging the right of the community's representative leaders to admonish and speak in the Lord's name.
Initially belonging to the ancient world, Christianity remains the faith of a high proportion of this planet's population. Its characteristic teachings and ideals still speak universally to mind and conscience in individuals, and still bond together communities across chasms of differences in education and race. To study the ancient Church is to watch the Christian society forming structures and social attitudes that have remained lasting and in the main stream permanent. The aspiration to be universal is rooted in monotheism. There is always a tendency for religions to become tribal; that is, each tribe looks to its own protecting god with whom sacrifices maintain friendly