One of my more quixotic quests has been to dispute the use of the term “Judeo-Christian” in normal conversation. Many people who use the term do so without much forethought, it’s just one of the definitions you use to point to the bracketing of the two traditional religions of Western civilization. In our modern context where there are great tensions between the world of Islam and the West it also alludes to a cleavage between the Abrahamic faiths where Islam is painted as the outgroup.
My own contention is that the term misleads, and emerged out of an attempt to acknowledge the rise of religious pluralism in what used to be called “Christendom,” that pluralism being tested on the margins by the predominant non-Christian tradition of the West, that of the Jews. As a matter of fact for most of the past 2,000 years, or more precisely the period between the Christianization of the Roman Empire (circa 300-500) and the Jewish Enlightenment (circa 1800), Jews were not part of Western civilization.* Rather, Jews were in the West, and in the Islamic World, but they were generally not of them, with the exception perhaps of Al-Andalus.
Of course the Christians share with the Jews much of the Hebrew Bible (there are minor differences due to the chain of translation). But the Judaism of the Bible which Christians are familiar with is not the dominant form of Judaism for most of the past 2,000 years. The Rabbinical Judaism which tied together most of the Jewish world over the past 2,000 years is a descendant of the sect of the Pharisees, and famously relies upon the extensive corpus of scholarship compiled in the Talmud, as well as a host of secondary commentaries. During the period of the Roman Empire there were Jews who rejected the vision of the Pharisees, often collapsed into the catchall label “Hellenistic Jews,” but these groups seem to have declined and gone extinct by Late Antiquity.** During the Medieval period there was a sect which rejected the Talmud, the Karaites, and some strands of modern Reform Judaism which stretches back to the 19th century espouse neo-Karaitism, and even assert that they are inheritors of the tradition of the Hellenistic Jews. But again, the point is that between 500 to 1800 Judaism existed at the sufferance of Christian and Islamic authorities, and that Judaism was Rabbinical Judaism (Christian authorities even persecuted Jews specifically when they deviated from Rabbinical Judaism, as only that religion was deemed an appropriate fossil witness for Christians to the superseded covenant). Many Jews converted to Christianity and Islam, but those who espoused the Jewish religion and adhered to Jewish law, Jewish Jews, were not mainstream participants in Western or Islamic civilization.
My own position from a phyolgenetic viewpoint is that Rabbinical Judaism, the dominant form of Judaism between 500 to 1800, resembles Islam much more than Christianity. Islam and Rabbinical Judaism have a more orthopraxic orientation (e.g., Halakah, Sharia) and less of a focus on Greek tinged theology than Christianity. I have pointed out before that Rabbinical Jews had arguments as to whether Christians were, or were not, monotheists, but agreed than Muslims were. I agree that some strands within both Judaism and Islam don’t fall into the bounds of this narrative, but these streams have been marginalized for most of the past 2,000 years, just as Judaizing movements within Christianity were never dominant or influential until the Radical Reformation (though I would contend that the Judaizing of most Radical Protestants is rather weak tea, and only notable due to the de-Judaization of Pauline Christianity). I am claiming here that the Great Tradition of Christianity is the outlier when it comes to the various strands of the Abrahamic faiths (along perhaps with the extreme rationalists among the Mu’tazili and various Jewish schismatic groups).
Why does this matter? Because the term Judeo-Christian makes everything I said above totally surprising. Rather, it might give the impression that what we know of as Reform Judaism was the norm for Judaism in the West for the past 2,000 years. I think a clustering of Reform Judaism with mainline Protestant Christianity is very plausible. What I’m trying to say is that if you had all the mainstream branches of Judaism and Christianity and generated a a phylogenetic tree, Judaism would be a paraphyletic class (Reform Jews being accepted as Jews, while Christians are not). But it isn’t only history that is misrepresented by the Judeo-Christian model, most people are rather ignorant, so trying to portray Islam as an outgroup to Judaism, instead of highlighting its similarities of character with Orthodox Judaism, simply wastes the opportunity to impart information-by-analogy to lazy people who can’t be bothered to learn anything about Islam. The reality is most ignorant people will remain that way, and will continue to talk about issues which relate to categories which they are grossly ignorant of (e.g., various religious sects and groups). “Judeo-Christian” compounds the follies of modal stupidity.
With all that said, perhaps I’m full of crap and don’t really know what I’m talking about. Tell me why! Why does the term Judeo-Christian really make sense? Remember that I agree that Judaism is the parent religion of Christianity, but I simply reject the contention that Rabbinical Judaism was the Judaism which was the parent religion of Christianity. And Islam is obviously also strongly shaped by Judaic models, and by the time Islam arose Rabbinical Judaism was the overwhelmingly dominant form of the religion, so by the criterion of Jews-as-antecedents I think Judeo-Islam still wins. Is Judeo-Islam more of an affront to reality over most of history since the emergence of the world of Islam than Judeo-Christianity? If you don’t seem to know anything about religion or history I’m not really going to publish your comment. Just a friendly notice.
* Baruch Spinoza was I think a forerunner of the 19th century “Confessionless Jew,” but not typical for his age.
** Some scholars argue that Christianity is actually a form of Hellenistic Judaism.