For an "ermergent" that is an incredibly non-emergent, narrow or closed minded and inaccurate comment.

When Christianity spread out from Jerusalem, the first place they went to were the Jewish communities throughout the Roman and Persian (Parthian) empires. Judaism was not limited to Judea and Galilee.

In the first place I did not say nor did I imply that "Judaism was limited to Judea and Galilee.  My point was that Judaism as a culture began with the house of Judah in the land of Judaea with its temple cult in the city of Jerusalem which was imported to Babylon by the Babylon captivity and from there spread until in the first century it could be said that there was a Babylo-Jewish synagogue (substitute for the temple) in nearly every city within the Roman Empire.  This "culture" came from predominently one tribe - the tribe of Judah and the ten tribes as an entity had no part in it.

Even if some of the legend of ‘lost tribes’ are true they have no bearing on this discussion as they had no contact with the writers and theologians of the early church and could not give them an authentic perspective on the language and culture of the bible.

I said nothing about "the legends" of "the lost tribes" which is  Jewish myth.  I know nothing of any "lost tribes" not does the Bible.

Your statement that the 10 tribes of Israel have "no bearing on this discussion" is incredibly naive at best and at its worst, is a vivid display of biblical ignorance. 

God’s plan for the ten tribes as set forth in the Bible has a great deal "of bearing on this discusion," your non-emergent attutude notwithstanding.

For starters I would suggest you take a very serious look at the statement "melo ha goyim"  (fulness of gentiles) as applied to Ephraim in Genesis 48:19 and 49:1 and its parallel in Romans 11:25-26 as explained by Paul in the first century context.