7.5 Christianity
It was religion to which the Roman Empire was to succumb in the fourth century A.D.  This was ultimately the legacy of a people whose language was virtually identical to that of the Phoenicians.
The founding figure, Jesus of Nazareth, was a Jewish popular preacher and miracle worker. He told his followers that the kingdom of heaven was at hand(Matthew 4:17) and urged them to adopt a touchingly altruistic morality (Luke 6:27-35). For largely political reasons he was subjected to the cruel, but not unusual, Roman punishment of crucifixion. This meant that he died like a common criminal alongside a couple of robbers, unable to save himself—so bystanders taunted—let alone others (Matthew 27:42). Yet this disaster proved to be the beginning rather than the end of a new religion. The followers of Jesus claimed that despite appearances he had been the Son of God, or God incarnate, and that he had willingly died on the cross to redeem mankind. Most of those who initially responded to this message were naturally local Jews, but the existence of a widely scattered Jewish diaspora meant that word spread quickly all over the Roman Empire. At the same time the early church was astute enough to customize the new faith for Gentiles by allowing them to join without taking upon themselves the irksome burdens of the traditional Jewish religious law (Acts 15:19-20). The outcome was that gradually the movement became overwhelmingly Gentile.
Like the Buddhists, the early Christians argued among themselves, and in due course they split up into a number of irreconcilable sects, despite (or because of) the deliberations of a series of councils. But in organizational terms the Christians differed from the Buddhists in significant ways. Whereas monks made up the core of the Buddhist community from the outset, Christian monasticism did not appear until some three centuries after the death of the founder. It then became a standard feature of Christian life, albeit eventually rejected by the Protestants; but it never took over. Instead, the core of the church was and remained a set of lay congregations under the authority of their priests, who in turn came to be subject to that of the local bishop.
A further contrast with the Buddhists was the extent of the overarching hierarchy that developed in Christianity above this local level. Buddhist sects in the early centuries had some kind of succession of patriarchs; but these rather shadowy figures do not seem to have matched the power of the handful of Christian patriarchs who came to hold sway over the church from their seats in the major cities of the empire. Of these, by far the most successful were the popes, who from their base in Rome were able to consolidate their authority over the western half of the empire. They thereby brought into being the Catholic church. This remarkable institution, despite its heavy penetration by the interests of rulers and others, has proved the most impressive and durable nongovernmental organization in the history of the world.
In the meantime the church's relations with the Roman emperors and their successors had changed drastically. The Christians had never plotted to overthrow the pagan empire; they were not like the Jewish Zealots, whose monotheist intransigence fed into a wildly imprudent rebellion against Roman rule in A.D. 66-70. But the Christians nevertheless picked a quarrel with the Roman state when, as part of their monotheist rejection of other gods, they refused to participate like loyal subjects in the standard rituals of emperor worship. Such attitudes led to intermittent persecutions of a kind that the Buddhists were usually spared, but not to a terminal catastrophe. Thus, by the early fourth century, there were apparently enough Christians for it to make sense for Constantine, a military claimant to the Imperial throne locked in conflict with his rivals, to identify himself with the Christian cause. He won his civil war, and by the end of the century Christianity was firmly established as the state religion.