What is the branch of Christianity?

Answer 1

If I understand the question correctly, there are three branches of Christianity: Catholic, Eastern Orthdox, and Protestant. Some may add a fourth beanch, Anglican, being that many see it as a "bridge" between (or merging of) Catholic and Protestant.

Answer 2

We do not know very much about Christianity in its earliest years. Some say that the Christians whom James, John and Peter led in Jerusalem and whom Paul met early in his missionary career were early Ebionites. Ebionites are considered to have been an early sect of Gnostic Christians. The two earliest known gospels were the Gospel of Mark and the Gospel of Thomas. Once again, the Gospel of Thomas was from the Gnostic branch of Christianity.

Paul is commonly believed to have taught a Christian gospel just like that which we find in the four New Testament gospels, but that is not necessarily true. Some of what we find in Paul's epistles seems strange alongside the gospel accounts. In any case, Paul speaks of false apostles who taught a different Christ, suggesting that already there were radically different views about who Christ was.

It seems possible that the earliest branch of Christianity may have been a Gnostic branch and that the forerunner of the Catholic-Orthodox branch only arose in the second half of the first century. The prism of modern belief will reverse this order, placing the Catholic-Orthodox branch first and delaying the start of Gnosticism until the second century.

In any case, the Gnostic branch went into serious decline and the Catholic-Orthodox branch became synonymous with Christianity. In time, the Coptic Church broke away, then the Great Schism of 1054 created separate Roman Catholic and Orthodox Churches.