We had a whole thread about why that particular term (even if often meant lovingly, and even by members of the faith) is probably a bad idea.
Probably best to avoid it, especially if you aren’t a member of the Jewish faith.
Back to the discussion of “full-blooded”. My family really can only be traced back to the great grandparents generation (various European Jews) for obvious reasons. As I related in another thread though, my Mother and Father in Law became enamored of Ancestry and similar sites, so got kits for my wife and myself. Hers came back as a wonderfully American mutt mix of all sorts.
Mine came back as 99+% Eastern European Jew. So, yeah, I’m as “full blooded” as far as genetic groupings matter. But they don’t. Humans can interbreed, have interbred, and will interbreed in the future. Matrilineally traced societies were an acknowledgement of the fact (at least in part, not going to assume in full or even in majority) that between unclear understandings of human inheritance and unclear human morality (
) that the male parent may be unknown, but outside of elaborate plots, the female is certain.
Rules and law are almost always built to cover generalities, where exceptional individuals may lay outside them. I doubt strongly that if we accept the premise of the thread (that an honest to god Messiah by OT terms) shows up, that they, having literally accomplished world peace, would in any way worry about such minor issues. Instead, if you believed you were a Jew, and especially practiced as a Jew, you’d likely be a Jew as far as they were concerned.
People like myself who are by upbringing and “blood” (continue to sneer at it, but I’ll use the term) but don’t consider themselves religious (although bringing world peace might make me reconsider!) might be asked to consider whether we want to be a full part of the people again, but can’t imagine it being forced.
So, IMHO (since it’s that forum) a person would arise, bring about world peace, and invite all those who considered themselves Jews to return to Israel for the consecration of a New Temple. That along with universal health and prosperity would be an accomplishment worthy of being a Messiah, and it’s a world I’d likely be happy to live in.