The main one is that the experience of Jesus in the life of these congregations was so real that people were prepared to die for it. Also christians loved each other and shared a common life - this was very attractive in the otherwise competitive atmosphere of the surrounding cultures.
The spread of Christianity was possible because of stability and unification of the Mediterranean achieved by Romans.
Christianity developed from a religion among a small group of Jews (who lived in Judea, which was part of the Roman Empire) into a mass religion in the Roman days. It spread around the Roman Empire. It became state religion. Catholic Christianity and Orthodox Christianity developed during the Later Roman Empire. They were originally called Latin or Western Christianity and Greek or Eastern Christianity respectively. The former was the main form of Christianity in the western part of the Roman Empire and the latter was the main form of Christianity in the eastern part of the Roman Empire.
A rift developed between Latin Christianity and Greek Christianity which then led to the schism between the Catholic and Orthodox Churches. The conflict between the two led to mutual distrust . The Orthodox Church was the church of the Byzantine Empire.
The spread of Christianity was possible because of stability and unification of Mediterranean achieved by Romans.
There was only one Roman Empire. Moreover, the Roman Empire did not study Christianity. An empire cannot study. The Roman Empire was where Christianity spread from Judea (which was a part of the Roman province of Syria). Both Catholic and Orthodox Christianity developed in the Roman Empire. Originally the were called Latin or Western Christianity and Greek or Eastern Christianity respectively. The former was the dominant form of Christianity in the western part of the Roman Empire and the latter was the dominant form of Christianity in the eastern part of this empire. There were also dissident Christian doctrines and sects.
The emperor Theodosius I declared Christianity to be the official religion of the Roman empire. In fact, he made Christianity mandatory for all.
Roman empire.
orthodox Christianity
The Roman Empire made Christianity the official religion of the Empire, and 'encouraged' the peoples it conquered to convert.
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After the Emperor Constantine converted to Christianity, that became the official religion of the Roman Empire.
Christianity was more than just famous throughout the Roman Empire. It spread and developed in this empire. Christianity started in the Roman Empire. Judea was part of the Roman province of Syria (that is, a province of the Roman Empire). The apostles and later Christian missionaries travelled around the empire and converted many people. The Christian churches developed in the Roman Empire. Christianity became a major religion of the empire and eventually became the state religion of the empire. Both the Catholic Church and the Orthodox Church were originally churches of the Roman Empire. The former was originally called Latin or Western Christianity and was the main version of Christianity in the western part of the empire. The latter was originally called Greek or Eastern Christianity and was the main version of Christianity in the eastern part of the empire.
paul spreaded christianity throughout the empire