Who Is a Jew — And Why Even a Heretic Can Still Come Home

6 Tishrei 5787 · 17 September 2026 · Ten Days of Teshuvah

We are inside the Ten Days — between the shofar of Rosh Hashanah and the seal of Yom Kippur. Elul already did its work of waking. The King is still near. These days are for return and judgment. They are not for writing Jews out of Jewry.

Yet people keep arguing about who is a Jew as if the noun were a mood, a coalition, or a costume. It is not. Covenant is older than the news cycle. The brit does not wait for comfort, and it does not dissolve because the categories are inconvenient.

This is a public clarification — for Diaspora and Israel alike. Not a hit piece. Not a party platform. Hold four distinctions carefully. Most of the confusion collapses. Then hold the hinge these days demand: even a heretic can do teshuvah. The covering can be lifted.

1. Status: yes or no — no “almost”

A Jew is a Jew because his mother is a kosher Jew, or because he truly converted through a rabbinical Bet Din. That is the gate. Yes or no. There is no “almost Jew.”

The Gemara in Kiddushin 68b reads Devarim 7:3–4 and teaches, in Rabbi Yoḥanan’s name from Rabbi Shimon ben Yoḥai: your son from a Jewish woman is called “your son”; your son from a gentile woman is not called your son, but her son. Status follows the mother. Rambam states the same in Hilchot Issurei Biah 15:4: a child born from a gentile or a maidservant “is like his mother”; “we are not concerned with the father.” Shulchan Aruch Even HaEzer 8:5 runs the same direction.

The other gate is gerut. Rambam (Issurei Biah 13:1–4): entry requires circumcision and immersion (and, in Temple times, sacrifice). Later generations who wish to enter the covenant and accept the yoke need circumcision and immersion. The yoke is not optional ornament. Shulchan Aruch Yoreh Deah 268 requires informing of mitzvot, receiving them, circumcision, immersion — with three fit to judge, by day. Kabbalat hamitzvot before a qualified court is indispensable. A certificate that treats Sinai as optional branding is not that gate.

Not a vibe. Not a surname. Not “I feel Jewish.” Kindness and politics do not rewrite lineage. Born of a Jewish mother and never opened a siddur — still a Jew by status. Did not pass the gate and did not complete true Bet Din conversion — not. Mercy without definition is erosion.

2. Living by the Jewish way: Halacha, via the Thirteen Principles

Status answers who is inside the people. It does not yet answer how one lives as a Jew.

The only way to live by the Jewish way is through Halacha — and Halacha is not a buffet. Its backbone of belief is clear in the Thirteen Principles of Faith as Rambam formulated them in his Commentary on the Mishnah to Sanhedrin 10:1 (Perek Chelek): G-d’s existence and unity; that He is not a body; that He is first; that He alone is rightly worshipped; prophecy; the prophecy of Moshe; Torah from Heaven; Torah’s immutability; that G-d knows the deeds of men; reward and punishment; the coming of Mashiach; and the resurrection of the dead.

After listing the thirteen, Rambam writes that one who believes them enters the category of Israel for love and brotherhood — and even if he sins from desire, he remains among the sinners of Israel with a share in the World to Come. That separates fidelity of foundations from sin of appetite. Culture and solidarity are obligatory. None substitutes for Halacha. None rewrites the Principles into a mood of the age.

A Jew may be distant, wounded, or angry and still be addressable for return. What he may not do is redefine the road and demand that Sinai salute. Atem nitzavim hayom kulchem (Devarim 29:9) was said under a brit, not under a brand.

3. Denial: still a Jew — and a heretic

Whoever denies this — maternal status as Halacha defines it, or that the Jewish way runs through Halacha and the Principles — is still a Jew if he is a Jew by status. He is a heretic. Those are different sentences. Mix them and you get cheap excommunication or cheap absolution.

Mishnah Sanhedrin 10:1 opens with mercy — “All of the Jewish people have a share in the World-to-Come” — then names exceptions: one who denies resurrection from the Torah, one who says the Torah is not from Heaven, and an epikoros. Rambam’s Hilchot Teshuvah 3:6–8 sorts the vocabulary: minim; apikorsim; those who deny the Torah (even one verse as not from Heaven; denial of Oral Torah; claim that the Torah has been replaced).

That severity is about belief, Olam HaBa, and faith-standing. It is not a license to un-Jew someone who entered by maternal lineage or true gerut. Rambam himself, listing those who forfeit a share in the World to Come if they die without repentance, still says they are “from Israel.” Sanhedrin 44a closes the cheaper door: even when they have sinned they are still called Israel — like a myrtle among thorns that is still called myrtle. Yisrael af al pi shechata, Yisrael hu.

Hold the registers apart: Jew by status; heretic by denial; living by Halacha — or not. A heretic remains claimable and accountable. Severity without the noun is another religion’s move. Mercy without naming heresy is flattery.

4. Neshama: the light remains — and the covering can be lifted

All Jews have a neshama. That is not sentiment.

Tanya, Likkutei Amarim chapters 1–2, following R. Chaim Vital: in every Jew — righteous or wicked — there are two souls. The second soul of a Jew is “truly a part of G-d above” (chelek Eloka mima’al mamash). The nefesh Elokit is not issued for good behaviour and cancelled for bad. The kelipah can thicken until the spark is inaudible. Sins cover the light. Ideology can bury it. The spark does not leave.

Tell a Jew he is not a Jew and the neshama yells from within. The work is not un-Jewing — it is uncovering.

The hinge: even a heretic can do teshuvah

Rambam does not leave the door slammed after he names minim, apikorsim, and deniers of Torah. In Hilchot Teshuvah 3:14 he asks when those harsh categories lose their share — and answers: when they die without teshuvah. If such a person returns and dies as a baal teshuvah, he receives a share, “for nothing stands in the way of teshuvah.” Even one who denied the fundamental principle (kafar ba’ikar) all his days, and at the end returns — he has a share. Any of the wicked, rebels, apostates and their like who return — openly or in private — are accepted.

Elsewhere Rambam warns the community not to be naive about certain heretics’ public repentance. That is caution about human acceptance, not Heaven’s closed door. High Holidays are not sentimental flattening — and not a locked gate.

Yisrael af al pi shechata means the covering has a name and the door stays open — without pretending denial is fidelity.

Why these days matter

Rambam places the year’s weighing on Rosh Hashanah; the beinoni hangs until Yom Kippur — if he does teshuvah, he is sealed for life. The shofar’s allusion is wake-up, inspect, return. Although teshuvah is always desirable, in the Ten Days it is especially desirable and accepted at once — “Seek G-d when He is found” (Yeshayahu 55:6).

The calendar refuses the cheaper politics of definition. Keep the noun. Name heresy. Leave the door open. The King is near — including a soul under a thick shell. Reception is not flattery. Accounting remains. Uncovering remains possible.

What this refuses

It refuses exporting a family fight into the definition. Politics does not rewrite who counts as a Jew. No faction picks which Jews count as conscience, and no faction dissolves the gate because it is hard. Categories first. The seasonal counterfeit — using judgment season to un-people the people instead of calling them home — is refused.

Simple table, old as Sinai

Noun: Jew. Covering: sin, ideology, denial. Avodah: uncover. Not: revoke. Not: redefine the gate until nothing remains. Season: Elul / RH / Ten Days / YK — return and judgment, not erasure.

That is the clarification. Guard the definition. Keep the noun. Name heresy where belief has ruptured. Leave return open without lying about the light under the shell — and remember, in these days especially, that even a heretic can still come home.

Sources (selected)

Kiddushin 68b; Devarim 7:3–4; Rambam Issurei Biah 12:7, 13:1–4, 15:4; SA Even HaEzer 8:5; SA Yoreh Deah 268; Rambam on Mishnah Sanhedrin 10:1 (Thirteen Principles); Mishnah Sanhedrin 10:1; Rambam Hilchot Teshuvah 2:6, 3:3–4, 3:6–8, 3:14; Sanhedrin 44a; Tanya, Likkutei Amarim 1–2.

Hedge: Rambam’s Ikkarim language about exiting the “category of Israel” names faith-standing / Olam HaBa rupture — not a gentile redo of maternal or gerut status. Teshuvah 3:14 keeps the door without cancelling 3:6–8 severity.

Companion: Yisrael Af Al Pi Shechata — A Jew Remains a Jew (definitional frame this piece states in public form).