For a long time, Messianic Jews have been affirming that Jewish identity is not nullified in Messiah. Many Gentile believers have heartily affirmed this truth as well. However, when it comes to "Gentile identity," some are left with questions. After all, Jewish identity seems (at least to some) to be easily identified as a rich heritage that is documented in the Scriptures and interwoven and extended through history and tradition. "But what does 'Gentile identity' even refer to?" some ask.
I think that this is a very good question and would like to see more efforts to explore possible, Biblical answers. I do think that Paul explicitly affirms “paternity” (in a very Roman fashion, btw), when he writes in Ephesians 3.14-15:
“For this reason I bow my knees before the Father, from whom every family (Greek patria literally “ancestry” or “family,” from the word pater, father) in heaven and on earth is named…”Roman societies organized themselves around family structures which had the father at the head. Here Paul seems to be building on that understanding with his claim that every “ancestry”is derived from the Father by virtue of the fact that it is literally named after Him.*