rationalskepticism.org

" ... which deals with the Christological controversies of the second and third centuries, as some Christians insisted that Jesus was human but not divine (e..g, the Ebionites and the Roman Adoptionists), others maintained that he was divine but not human (the opponents of 1 John and Ignatius, and then Marcion), others claimed he was two entities, a human Jesus who was temporarily inhabited by a divine being from the heavenly realm (the Gnostics), and others who claimed he was just one entity who was both divine and human.

That final choice won the debates, but all that did was start up a whole other round of debates. Some church leaders insisted that the man Jesus was God, and that God was God, and that therefore Jesus the Son was also God the Father – one God who was both son and father (kind of like I myself am both a son and a father – depending on whom I am relating to). That view was wildly popular for a time – it apparently was the majority view around the beginning of the third century – but it got trounced by theologians like Hippolytus and especially Tertullian. But then Origen came along with his theory of how it all worked – which also made sense to some people at the time, but later also came to be declared a heresy."

http://ehrmanblog.org/explaining-myself/