Early Christianity facts
Since the 19th century, historians have learned more about the early Christian community. Books written early in the time period, such as the Didache (in second-millennium copies) and the Gospel of Thomas (in two manuscripts dated as early as about 200 and 340) as well as parts from the Jewish-Christian Gospels have been found again in the last 200 years
At the beginning of Christian history, the church was in Jerusalem, in an "upper room" perhaps where the Cenacle is today, and leaders included James, Peter, and John. The major source for the Apostolic Age (c.30-c.100) is the Acts of the Apostles. Following the Great Commission, the missionary actions of the Apostles, including Paul of Tarsus who said the title of "Apostle to the Gentiles", spread Christianity to cities in the Hellenistic world, such as Alexandria and Antioch, and also to Rome and even beyond the Roman Empire. The term "Christian" was first applied to members of the church at Antioch according to Acts 11:26. The New Testament includes letters written by Paul to churches, such as those in Thessalonica and Corinth, during the years 50-62, see also Seven Churches of Asia. Early Christians continued the Jewish practice of respect for the Jewish Scriptures, using the Septuagint translation of Hellenistic Judaism that was in general use among Greek-speakers, or the Targums in use among Aramaic-speakers, but added to it their own writings.
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