I have a different perspective on this.
One of my parents was Jewish, the other Christian.
The fact that my father married a "shikse" caused the Jewish side of the family to disown my father.
The fact that my mother married a Jew drove the Christian side of the family into an equal panic.
What they overlooked, was that there was an innocent child involved.
I will be waiting for all of them in Hell, because MY God has promised me they will all go there - every one of them, for their arrogance and intolerance and religious self-righteousness.
There, they will have *me* to contend with.
Deal with it.
The Father. The Mother, and the Master of the Universe.
That's why some people have certain divine attributes which are not dependent upon their genes.
I am the child of a Jewish father and a Christian mother.
I guess I could be Jewish according to two sects of Judaism but I'm not now-because I converted to Christianity in my 20's while I was in the service.
I married a Jewish woman back in the days religion didnt matter to me, and over the years we have had two kids.
The problems of the world today arent going to pass over my house and leave me alone just because I am not up to Halacha standards, or in accordance with a Church Doctrine.
Half Jews, Crypto Jews, mamzers, whatever you call us, we have a unique insight into the topics of this discussion. I think somewhere along the line, we have a destiny to fulfill in this equation as well. I don't exactly know what it is.
On the topic at hand, I think Rabbi Rosensweig spelled it out best when he wrote the "Star of Redemption" theory. Christianity is evangelical and destined to spread the word to the world. Judaism is the corporate knowledge. Christianity brings people to G-d. Jews are already with G- and dont need to be brought into the fold.
Thats my .02