Who Is a Jew? The Two Ways Jewish Identity Is Determined

"Who is a Jew?" sounds like it should be a simple question. But you would be amazed how many different answers people give. Is a Jew someone who observes Jewish law? Someone who lives in Israel? Someone who believes in a particular set of ideas? Someone who has Jewish ancestry?

The options and opinions are many, but according to Jewish law the answer is actually straightforward. There are exactly two ways to be a Jew.

Jewish Through Matrilineal Descent

If your mother is Jewish — through an unbroken chain of Jewish mothers going back through the generations — then you are Jewish. Period. It does not matter if you are observant or not. It does not matter if you have ever set foot in a synagogue. If your mother is Jewish, you are a Jew.

Here is what often surprises people: if your father is Jewish but your mother is not, you are not considered Jewish according to Orthodox Jewish law. And the reverse is also true — if your mother is Jewish and your father is not, you are fully Jewish.

This matrilineal principle is a core element of Jewish law and has been the standard for thousands of years.

Jewish Through Conversion

The only other way to become Jewish is through a proper conversion to Judaism, performed under the authority of an Orthodox beis din (court of Jewish law). Conversion is a serious process that involves study, commitment to observing the mitzvos (commandments), and immersion in a mikvah (ritual bath). For men, it also includes circumcision.

Once a person has completed a legitimate conversion, they are fully Jewish — as Jewish as someone born to a Jewish mother. And their children, born after the conversion through Jewish matrilineal descent from the mother, are Jewish as well.

Once Jewish, Always Jewish

Here is something that many people do not realize: according to Jewish law, a Jew cannot stop being Jewish. Even if a Jewish person converts to another religion, they are still considered Jewish — a Jewish person who has made a serious mistake, but Jewish nonetheless.

Even if someone's family has not practiced Judaism for many generations, as long as their matrilineal descent is Jewish, they need no conversion. They are a Jew just like any observant Orthodox Jew. The neshama (soul) of a Jew is eternal, and no decision or circumstance can erase that identity.

Why This Matters

Jewish identity is not a membership you sign up for and cancel when it no longer suits you. It is not about what you believe or how you practice. It is about who you are — at the deepest level of your soul.

I have met people who discovered late in life that their mother's mother was Jewish, and they were stunned to learn that according to Jewish law, they had been Jewish all along. That is the power of this principle. Being Jewish is not something you do. It is something you are.

So now you know the answer to "who is a Jew." It is simpler than most people think — and more profound than most people realize.

The Conversion Path

For those not born Jewish, conversion to Orthodox Judaism is possible — but it is rigorous. It requires years of study, full integration into an Orthodox community, commitment to keeping all the commandments, and approval by a rabbinical court (beit din). The process is deliberately thorough because the commitment is permanent and total.

Once a person converts through a valid Orthodox beit din, they are 100% Jewish — with no asterisk, no qualification, no second-class status. The Torah specifically commands love for the convert, and this commandment appears 36 times. In our community, converts are deeply respected.

Why This Matters Today

The question "who is a Jew" is not academic. It affects:

• Marriage: An Orthodox Jew can only marry another Jew. If there is doubt about someone's Jewish status, it must be resolved before a wedding can proceed.
• Religious obligations: Jewish status determines whether someone is obligated in the 613 commandments, counted in a minyan, or called to the Torah.
• Israel's Law of Return: The State of Israel grants citizenship to Jews — but the definition used by the Israeli rabbinate differs from the Law of Return's broader definition, creating ongoing tensions.
• Denominational disagreements: Orthodox Judaism does not recognize Conservative or Reform conversions. This creates painful situations where someone considers themselves Jewish but is not recognized as such by Orthodox authorities.

Common Questions

What makes someone Jewish? In Orthodox law, a person is Jewish if their mother is Jewish (matrilineal descent) or if they undergo a valid Orthodox conversion. A Jewish father alone does not make someone Jewish according to Orthodox halacha.

Can you be half Jewish? In Orthodox law, no — you are either Jewish or not. If your mother is Jewish, you are fully Jewish regardless of your father's religion. If only your father is Jewish, you are not Jewish according to Orthodox halacha (though Reform Judaism counts patrilineal descent).

Can you stop being Jewish? According to Jewish law, once someone is Jewish (by birth or conversion), they remain Jewish permanently — even if they stop practicing or convert to another religion. A non-practicing Jew is still Jewish.