According to the Israeli chief rabbinate, a Jew is a person known to be a Jew. They apply the reasoning that errs on the side of “putting a fence around Torah”, meaning to not risk any assimilation of foreign thought, tradition, that could dissolve in any way the teachings of Torah and as interpreted by rabbis.
The effort to “put a fence around Torah” is driven by the fear of offending God, the fear of misrepresenting divine intent, an application of ‘better safe than sorry’.
To the Israeli chief rabbinate, there is no default that one is a Jew, regardless of how one represents themselves. There is the requirement to prove positively. You are not a Jew unless you assertively prove that you are a Jew.
According to halacha, there are two ways to be a Jew legally. One is by virtue of one’s birth. Jewish racial identity is passed matrilineally, if one’s mother was Jewish, then you are Jewish. That applies to both self-identifying and distinct Jewish children of Jewish mothers, AND to assimilated or even converted children of Jewish mothers.
The population of those that are Jewish by that racial halachic definition is exhaustive, and comprised MOSTLY of those that do not identify externally as Jewish, or even know that they are Jewish.
If a Jewish mother has only one child, the likelihood that the child will be female and the Jewish gene will be conveyed is 50/50. Two generations in a row of one child, the likelihood is only 25% that the grandchild will be Jewish. If the average family size is more than one, then approximately 50% of the subsequent children will be Jewish even if they don’t know it.
For those families that marry within the Jewish community, the likelihood of Jewish descent is 100%, the rabbinic “sure thing” (no gamble).
The question though is to how to know if a stranger that a Jew encounters is Jewish or not. For personal identification, it’s not a big deal. People can avoid others on any trivial or profound, substantative or prejudicial basis. For political rights in a democracy (even a professed Jewish democracy), it is a big deal.
According to Jewish writings, 10 of the 12 original tribes assimilated or converted. That means that if proportional, 5/6 of the world’s Jewish population doesn’t have any way to determine if they are Jewish or not.
Another virtuous form of the fear of offending God, is the fear of being too restrictive, in this case of assaulting Jews inadvertently, halachically legal Jews among Palestinians, Lebanese, Iranians, etc. Orthodox assert daily as a prerequisite to prayer, “I hereby take upon myself the obligation to love my fellow man as myself”. That is the golden rule, interpreted in Christian ideal as applying to all human beings. It is the basis of non-violent civil disobedience for example. Most orthodox think of that as applying to the Jewish community, members of the shtetl in particular.
While, there is certainly religious support for defending against actual aggressing enemies, the question of whether it is acceptable to unilaterally discriminate or aggress against civilians is a very different religious question.
It’s a similar question to the old ethical cliché (a great one), of “the person you are speaking to may be the “messiah””, a predisposition of respect and attention rather than a predisposition of aggression and distrust.
The second substantive meaning of the question of “who is a Jew?” relates to the Torah defined mission of the Jewish people, the purpose that we were instructed to remain as a coherent people, rather than only be assimilated. That is to serve as “a nation of priests”. Substantively, that means to transform, to offer to the One the components of the world, towards removing the obstacles to coherence (sin) or of making what is incomplete and disparate complete and coherent.
In addition to being Jewish by birth, to the orthodox, there is a path of conversion. One may become Jewish, or affirm one’s latent “Jewishness”, by voluntary transformation, achieved through prayer, personal disciplines, study, good deeds.
So, what is a “Jewish soul” in that respect? My sense is that a large component of that is the instinct to make things whole, to heal interpersonal relations, to heal ill-health, to accomplish good even through business, and some in the form of politics (though I think that is a necessary but small component of the instinct of tikkun olam).
Whether that instinct is a “Jewish” instinct or a human one is irrelevant to me. What I recognize is a member of the “brit”, the healing conspiracy. The specifics are in the nature of appealing to a non-form, transcendental and simultaneously immanent One. It is an “irony” to me that Muslims participate in that worship of the One without form, and should comprise a basis of mutual respect (if it were not for the trappings of each). We should be primarily allies, and only incidentally adversaries. People aren’t that humble though (too many Jews and too many Muslims). Both communities proceed morally beyond successfully doing their work, and instead emphasize how wrong the other is, rather than how complementary.
When I meet a Muslim that heals in the way that I apply the Jewish mission, I don’t offend them by saying overtly that I consider them a member of the “brit”, but a part of me thinks of them in that light, with respect, a kindred spirit (with some limits),a supporter of the conspiracy for good.
Similarly, when I meet an activist that is essentially motivated by compassion for all, is warm-hearted to all genuinely, and seeks the greater good from intimate to political (more than just applying ideology), I see a kindred spirit.
To my mind, the Jewish mission, the covenant of Jewish obligation to cultivate the sensitivity and skillsets to make whole what is disparate is critical to continue. I will and do “teach my children”, both racially through mother’s genes and culturally through pragmatic compassion, prayer and good deeds.
Israeli law does not affirm the fear of offending the 5/6+ that are legally Jewish but don’t know it, nor can anyone on the planet accurately determine. And, Israeli and Jewish community do not affirm the relevance of those Jewish and non-Jewish conspirators to the positive mitzvah of making real peace/coherence in the world.
So, in that sense we are confused, and need good soulful guidance and support.
The formation of Israel remains a religious gamble. 60 years ago, most that assessed the state of Israel through a religious perspective regarded it as an exception, a diversion or even an affront on God’s “will”. A minority conceived as Israel as the equivalent of instructions to Joshua, ‘conquer, but know that it is God’s action that is making it happen, not yours’. Its hard to know if that military as agent for God’s will is still the minority view.
The proof in the pudding though is NOT the successful conquering, even over a hundred years, but the real Jewish mission of achieving peace, justice and coherence and making a Jewish state that is Jewish substantively (conforming to the ethical commandments, “If you keep my commandments, I will give you the rain in its time….”), and not only in name.
Even for the neo-religious, the exclusive Jewish definition is at best a secondary means to a larger end. “My sanctuary will be a house of prayer for all the nations.” We should keep our eye on the prize.