Daf Yomi
Chullin 92
In another voice
Sugya Map
The ninety-second folio of Tractate Chullin serves as a grand intellectual junction, weaving together celestial liturgy, the symbolic landscape of patriarchal history, the socio-political structures of the exilic Jewish world, and the precise, razor-sharp anatomical boundaries of the prohibition of the sciatic nerve (gid ha-nasheh).
The sugya progresses through several distinct conceptual movements:
- The Liturgical License of the Heavenly Choirs: The mechanics of angelic song (Kedushah). Does the permission to utter the Divine Name depend on a quantitative threshold of praise?
- Nafka Mina: The permissibility of human liturgical innovations, the hierarchy of the Ofanim versus the Seraphim, and the ontological status of Israel’s prayer relative to the ministering angels.
- Primary Sources: Ezekiel 3:12, Hosea 12:5, Isaiah 6:3.
- The Metaphorical Vine and Exilic Authority: Homiletical decodings of Pharaoh's butler's dream Genesis 40:10 and Hosea's prophecies Hosea 3:2.
- Nafka Mina: The metaphysical distribution of the forty-five tzaddikim (righteous protectors) between Babylonia and Eretz Yisrael; the cosmic role of the Exilarch (Resh Galuta) and the Prince (Nasi); the structural role of the unlearned (am ha-aretz) in preserving the scholars (talmidei chachamim).
- The Anatomy of the Sciatic Nerve (Gid HaNasheh):
- The "Spoon" of the Thigh (Kaf HaYerech): Does the prohibition apply to birds? The dilemma of physical deformity versus species classification (min).
- The Fetal Sciatic Nerve and Fetal Fat: Does a late-term fetus (ubar) possess independent halakhic status, or is it subsumed within the mother’s slaughtering (ubar yerech imo)?
- The Ontological Status of the Gid: Is the gid considered "wood" (etz)—meaning tasteless and thus outside the standard definitions of food—or is it food (ochel)?
- The Purging of the Kidneys: The scraping of the white fat (shumana de-kulyata) and the removal of the kenokanot (tendril-like nerve fibers).
- Primary Sources: Genesis 32:33, Mishnah Chullin 89b, Chullin 92a–b.
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Text Snapshot
כיון דאתיהיב רשותא — אתיהיב.
"Once permission has been given [to mention the Name], it is given."[^1]
האי אומה כגפן היא מדמה: זמורות שבה — אלו בעלי בתים, אשכולות שבה — אלו תלמידי חכמים, עלין שבה — אלו עמי הארץ, קנוקנות שבה — אלו ריקנין שבישראל... שלחו מתם: לבעי רחמי אשכולות על עליא, דאלמלא עליא לא מתקיימי אשכולות.
"This nation is compared to a vine: Its branches—these are the homeowners; its clusters—these are the Torah scholars; its leaves—these are the ignoramuses; its tendrils—these are the empty ones of Israel... They sent from there [Eretz Yisrael]: Let the clusters pray for the leaves, for were it not for the leaves, the clusters would not survive."[^2]
אמר רב יצחק בר שמואל בר מרתא אמר רב: לא אסרה תורה אלא קנוקנות שלה. ועולא אמר: גירדא דאופתא הוא, ואסרה רחמנא.
"Rav Yitzchak bar Shmuel bar Marta said in the name of Rav: The Torah prohibited only its tendrils. But Ulla said: It is merely a scrape of wood, yet the Merciful One prohibited it."[^3]
Philological and Grammatical Nuances
- קנוקנות (Kenokanot): Used in two wildly different contexts on our daf. In the aggadic portion, it refers to the thin, curling tendrils of the vine—representing the "empty ones" (reikanin) of Israel. In the halakhic portion, it refers to the thin, capillary-like nerve fibers branching off the main trunk of the sciatic nerve. The linguistic bridge is clear: both represent the structural, non-essential, yet protective outer fringes of a central body.
- גירדא דאופתא (Girda d'Ofta): Literally "a scraping of a piece of wood." Ulla uses this vivid Aramaic idiom to denote complete tastelessness. If the gid is structurally equivalent to dry wood, it lacks the halakhic status of ochel (food). This sets up a profound chakira (conceptual inquiry) regarding whether the prohibition of gid ha-nasheh is an objective prohibition on a foodstuff, or a formal, metaphysical decree (gzeirat ha-katuv) on an anatomical entity regardless of its culinary properties.
- השופי (Hashufi): From the root ש-פ-ה, meaning to smooth, shave, or level. In the dispute of Rabbi Meir and Rabbi Yehuda regarding the fat of the nerve, hashufi denotes cutting the nerve and its fat flush with the surrounding muscle tissue, as opposed to excavating (meḥatetz) the deep, embedded roots.
Readings
The Rishonim and Acharonim divide over three major axes in our sugya: the mechanics of angelic liturgy, the halakhic status of the fetus, and the physical definition of the gid.
┌─────────────────────────────────┐
│ Chullin 92a Interpretations │
└────────────────┬────────────────┘
│
┌─────────────────────────────┼─────────────────────────────┐
▼ ▼ ▼
┌─────────────────┐ ┌─────────────────┐ ┌─────────────────┐
│ Angelic Liturgy │ │ Fetal Status │ │ Status of Gid │
│ (Ofanim vs. │ │ (Ubar Yerech Imo│ │ (Ke-Etz vs. │
│ Seraphim) │ │ vs. Ubar) │ │ Ochel) │
└────────┬────────┘ └────────┬────────┘ └────────┬────────┘
│ │ │
┌───────┴───────┐ ┌───────┴───────┐ ┌───────┴───────┐
▼ ▼ ▼ ▼ ▼ ▼
Tosafot: Ritva: R' Meir: R' Yehuda: Ulla: Rav:
Structural Spatial/ Ubar is Ubar is Gid is wood; Torah only
Symmetry of Servant Independent; Subsumed; Gzeirat prohibited
Spiritual Ontology Slaughter Shechitah HaKatuv tasty
Anatomy (Low vs. Required Clears Applies Tendrils
High) All Directly (*Kenokanot*)
1. Angelic Liturgy and the Hierarchical Paradox
The Gemara distinguishes between the Seraphim—who must wait for three words of praise ("Holy, holy, holy") before pronouncing the Tetragrammaton—and the Ofanim, who say "Blessed be the glory of the Lord from His place" Ezekiel 3:12, uttering the Name after only one word (Baruch).
Tosafot: The Structural Symmetry of Spiritual Anatomy
Tosafot ask why we merge these categories in our daily liturgy (Yotzer), saying "And the Ofanim and the holy Chayot... say: 'Blessed...'"[^4] This implies the Chayot also say Baruch, yet they are higher than the Ofanim.
Furthermore, Tosafot confront the contradiction between our sugya and Hagigah 13b, where the Gemara compares the wings of the Chayot (four) to the Seraphim (six). If they are entirely distinct classes of angels, why does the Gemara assume they should be structurally identical?
Tosafot’s chiddush is that despite functional and liturgical differences, there is a structural symmetry in spiritual anatomy. Just as the Ark built by Moses and the Ark built by Solomon shared identical conceptual blueprints despite their physical and temporal differences,^Mishnah Avot 1:2 so too do celestial beings share a common baseline template.
The Ritva: The Spatial/Servant Ontology
The Ritva offers a radically different reading.^Ritva on Chullin 92a:1 He notes that Rashi views the Ofanim as superior to the Chayot and Seraphim. The Ritva rejects this, citing Ezekiel 1:20: "For the spirit of the living creature (Chayah) was in the wheels (Ofanim)"—proving the Chayot are the driving spiritual force.
Why, then, are the Ofanim allowed to utter the Divine Name with fewer introductory words?
The Ritva introduces a brilliant conceptual model: The Servant Privilege of Lower Beings. The Ofanim are spiritually closer to the physical world (krovim la-aretz). Because of their lower status, they are viewed like low-level household servants. A king does not demand elaborate protocol from the stable boy; the servant simply states his message and uses the King's name.
However, the Chayot and Seraphim—and indeed, Keneset Yisrael—are noble counselors. If a high minister approaches the King without the proper three-part formula of deferential protocol, it is an affront to the royal dignity. Thus, the strictness of the liturgical protocol is a function of proximity and nobility, not inferiority.
2. Fetal Autonomy and the Metaphysics of Ubar
The Mishnah states that the prohibition of gid ha-nasheh applies to a fetus (ubar). Rabbi Yehuda disagrees, permitting both its gid and its chelev (fat).
Rabbi Meir: The Independent Entity (Ubar Lav Yerech Imo)
For Rabbi Meir, a late-term fetus (specifically a nine-month-old fetus found alive after the mother's slaughter) is considered an independent animal (behemah bifnei atzmah). Because it is structurally and halakhicly distinct from its mother, the slaughter of the mother (shechitat imo) does not extend its purifying effect to the fetus’s forbidden fats or its sciatic nerve.^Chullin 74a
Consequently, the fetus requires its own independent act of shechitah to be permitted for consumption, and its chelev and gid remain strictly forbidden under the standard Torah prohibitions.
Rabbi Yehuda: Subsumed Existence (Ubar Yerech Imo)
For Rabbi Yehuda, the fetus is merely "the thigh of its mother" (ubar yerech imo). It is an organ of the maternal body.
The profound chiddush here—expounded upon by the Acharonim (see the Kehillot Yaakov)[^5]—is that when the mother undergoes shechitah, this act of slaughter does not merely permit her meat; it permits everything structurally subsumed within her body.
Because the fetus is an organ of the mother, the mother's shechitah completely clears the fetus's meat, its chelev, and its gid. There is no independent halakhic framework for the fetus; its reality is entirely maternal.
3. The Ontological Status of the Gid: Wood vs. Food
The core halakhic debate between Rav and Ulla on Chullin 92b concerns the physical reality of the sciatic nerve.
┌─────────────────────────────────────────┐
│ Is the Gid Hanasheh Food or Wood? │
└────────────────────┬────────────────────┘
│
┌─────────────────────────────┴─────────────────────────────┐
▼ ▼
┌─────────────────────────────────┐ ┌─────────────────────────────────┐
│ Rav's Position │ │ Ulla's Position │
├─────────────────────────────────┤ ├─────────────────────────────────┤
│ • Gid is "Wood" (Tasteless) │ │ • Gid is "Wood" (Tasteless) │
│ • Torah only prohibits edible │ │ • Torah issued a formal Decree │
│ parts (Tendrils/Kenokanot) │ │ (Gzeirat HaKatuv) anyway │
│ • No liability for eating the │ │ • Liable for eating the main │
│ main tasteless nerve trunk │ │ tasteless nerve trunk │
└─────────────────────────────────┘ └─────────────────────────────────┘
Rav: The Flavor-Based Prohibition
Rav posits that because the main trunk of the sciatic nerve is tasteless (girda d'ofta), the Torah could not have prohibited it. The Torah does not prohibit wood; it prohibits food (ochel).
Therefore, Rav’s chiddush is that when the Torah prohibited the gid, it was referring exclusively to the kenokanot—the capillary-like nerve fibers that run alongside the nerve and are embedded in the muscle tissue. Because these fibers absorb flavor from the surrounding meat and fat, they possess the culinary status of food.
The main, hard trunk of the nerve remains exempt from biblical liability.
Ulla: The Formal Anatomical Decree
Ulla agrees with Rav's physical description—the nerve is indeed tasteless wood—but rejects his halakhic conclusion.
Ulla’s chiddush is that the prohibition of gid ha-nasheh is a formal anatomical decree (gzeirat ha-katuv). The Torah did not prohibit the gid because of its culinary properties, but because of its historical-metaphysical significance (commemorating Jacob's struggle with the angel).
Therefore, the lack of flavor is irrelevant. The Torah formally designated this specific anatomical structure as forbidden, stripping away the standard requirement of ta'am (flavor) for dietary prohibitions.
Friction
1. The Angelic Wing Contradiction
The Kushya
In our sugya, the Gemara asserts that the Ofanim are the ones who utter the verse "Blessed be the glory of the Lord from His place" Ezekiel 3:12. The Seraphim, however, say "Holy, holy, holy" Isaiah 6:3.
Yet, in Hagigah 13b, the Gemara engages in a complex discussion regarding the reduction of angelic wings. It quotes Isaiah 6:2 ("Each one had six wings") and contrasts it with Ezekiel 1:6 ("And every one had four faces, and every one of them had four wings"). The Gemara there resolves this by stating that the destruction of the Temple caused a reduction in the number of wings from six to four.
The underlying assumption of Hagigah 13b is that the Seraphim (from Isaiah) and the Chayot (from Ezekiel) are comparable, if not identical, spiritual entities whose anatomical structures can be mapped onto one another.
But if Chullin 92a is correct that they are entirely different classes of angels with distinct liturgical rules (the Seraphim waiting for three words, the Ofanim/Chayot waiting for fewer), why does Hagigah 13b treat them as a singular, continuous class of beings whose wing-count can be directly contrasted?
┌───────────────────────────────────────┐
│ The Angelic Wing Contradiction │
└───────────────────┬───────────────────┘
│
┌───────────────────────┴───────────────────────┐
│ How can Hagigah 13b contrast Isaiah's │
│ Seraphim (6 wings) with Ezekiel's Chayot │
│ (4 wings) if they are distinct classes? │
└───────────────────────┬───────────────────────┘
│
┌───────────────────────────────┴───────────────────────────────┐
▼ ▼
┌─────────────────────────────────┐ ┌─────────────────────────────────┐
│ Tosafot's Resolution │ │ Maharsha's Resolution │
├─────────────────────────────────┤ ├─────────────────────────────────┤
│ • Structural Symmetry template │ │ • Historical Metamorphosis │
│ • Different classes but share │ │ • Destruction of the Temple │
│ the same baseline blueprint │ │ shrank the celestial structure│
│ (like the Arks of Moses/Sol) │ │ collapsing distinct classes │
└─────────────────────────────────┘ └─────────────────────────────────┘
The Terutzim
Tosafot's Solution
Tosafot (Chullin 92a s.v. Baruch Ofanim) explain that indeed, they are distinct classes. However, we apply a principle of Structural Symmetry.
Tosafot cite the Gemara in Yoma 72b, which contrasts the Ark of the Covenant built by Moses with the one built by Solomon. Even though they were completely different physical objects, the Gemara assumes that what applied to one applied to the other because they represent the same archetypal form.
So too with the angels: although Seraphim and Chayot occupy different rungs on the celestial ladder, they share the same baseline blueprint. Therefore, any reduction in spiritual capacity (represented by the loss of wings) must affect both classes symmetrically.^Tosafot on Chullin 92a:1:1
The Maharsha's Solution
The Maharsha (Hagigah 13b) takes a more historical-metaphysical approach. He argues that the transition from six wings to four was not merely a passive change in individual angels, but a historical metamorphosis of the entire celestial hierarchy.
When the Temple was destroyed, the higher class of Seraphim retracted their presence, and the Chayot were demoted in their capacity, effectively collapsing the distinctions that existed during the First Temple era. Thus, the comparison of wings is a comparison of eras, not just static species.
2. Shmuel's Paradox of Fetal Fat
The Kushya
The Gemara on Chullin 92b quotes Shmuel: "When the Mishnah states 'And its fat is permitted,' this is according to everyone."
The Gemara immediately challenges this: How can Shmuel claim this is unanimous? We have an explicit Baraita where Rabbi Meir and Rabbi Yehuda argue about the fetus!
- Rabbi Meir: "The sciatic nerve applies to a fetus, and its fat is prohibited."
- Rabbi Yehuda: "The sciatic nerve does not apply to a fetus, and its fat is permitted."
Clearly, this is a direct, tannaic dispute. How could Shmuel assert that the permissibility of the fat is "according to everyone"?
The Terutz
The Gemara resolves this by redefining the referent of Shmuel's statement. Shmuel was not referring to the fat of the fetus (chelev ubar), but rather to the fat of the sciatic nerve itself (chelev gid ha-nasheh).
Even Rabbi Meir, who prohibits the sciatic nerve, agrees that the fat surrounding the nerve is biblically permitted.
┌────────────────────────────────────────┐
│ Shmuel's Paradox of Fetal Fat │
└───────────────────┬────────────────────┘
│
┌───────────────────────┴───────────────────────┐
│ How can Shmuel claim unanimity when R' Meir │
│ and R' Yehuda explicitly dispute fetal fat? │
└───────────────────────┬───────────────────────┘
│
▼
┌────────────────────────────────────────┐
│ The Gemara's Terutz │
├────────────────────────────────────────┤
│ • Shmuel referred to the fat of the │
│ *sciatic nerve* itself, not the fetus│
│ • All agree this fat is Biblically │
│ permitted (though Israel is holy and │
│ adopted a Rabbinic/customary ban) │
└────────────────────────────────────────┘
But this terutz immediately triggers a secondary problem: Do they really agree on the fat of the nerve? We have another Baraita:
- Rabbi Meir: "One scrapes around it [the nerve]... and cuts out its fat from its source [deep inside the meat]."
- Rabbi Yehuda: "One cuts it level with the flesh [flush], but does not scrape it from its source."
This shows that Rabbi Meir prohibits the deep fat of the nerve, while Rabbi Yehuda permits it!
The Gemara answers: Shmuel concedes that according to Rabbi Meir, the fat of the nerve is permitted by Torah law (d'oraita). The dispute between Rabbi Meir and Rabbi Yehuda is entirely Rabbinic.
The Baraita states: "Its fat is permitted [by Torah law], but the Jewish people are holy and treated it as forbidden." Rabbi Meir holds this holiness-custom has the force of a full Rabbinic decree, requiring deep excavation (meḥatetz), whereas Rabbi Yehuda holds the custom only went so far as to forbid the surface fat (hashufi), leaving the deep roots permitted.
Thus, at the level of Biblical law, Shmuel’s assertion of unanimity stands.
Intertext
1. The Noahide Code and the Liturgical Boundaries of Perversion
Our sugya features a famous dictum by Ulla regarding the thirty commandments that the descendants of Noah accepted upon themselves, of which they only maintain three:
שאין כותבין כתובה לזכרים, שאין שוקלין בשר המת במקולין, ושמכבדין את התורה.
"That they do not write a marriage contract (ketubah) for males, that they do not weigh the flesh of the dead in butcher shops, and that they honor the Torah."[^6]
This passage provides a profound insight into the halakhic understanding of societal decay and the limits of moral degradation.
The Rambam's Codification
The Rambam codifies the general obligation of Noahides to establish a judicial system (dinim):
וכיצד מצווין הן על הדינין? חייבין להושיב דיינין ושופטים בכל פלך ופלך לדון בשש מצות אלו, ולהזהיר את העם...
"And how are they commanded regarding laws? They are obligated to set up judges and courts in every district to judge these six commandments, and to warn the people..."[^7]
Conceptual Analysis: The Institutionalization of Sin
Why is the writing of a ketubah for males singled out, rather than the act of homosexuality itself (which is a capital offense under the Noahide code)?^Sanhedrin 56b
The Meiri explains that the critical threshold of societal collapse is not the commission of a sin, but its institutionalization.^Meiri on Chullin 92a A society can survive individuals committing transgressions in private.
However, when a society drafts a legal document—a ketubah—to formalize, validate, and celebrate a relationship that violates the natural order, it has crossed an ontological line. The ketubah represents the co-opting of the framework of holy covenant to sanctify perversion.
By refraining from writing a ketubah, the Noahide world, even at its lowest point of moral decline, maintains a vestigial respect for the concept of formal legal covenant.
2. The Metaphysics of Gid Ke-Etz (Tastelessness in Halakha)
Ulla’s position that the gid is like wood (girda d'ofta) yet forbidden by Biblical decree has massive ramifications across the laws of Kashrut.
The General Rule: Achilat Issur She-lo Ke-derech Achilato
Generally, one who eats a forbidden substance in an atypical manner (she-lo ke-derech achilato)—such as eating raw, dry, or completely tasteless material—is exempt from biblical liability.^Pesachim 24b
If the gid is tasteless wood, why is there liability?
The Minchat Chinuch explores this deeply.^Minchat Chinuch 3 He asks: If the gid is wood, does it require the minimum volume of a kezayit (the volume of an olive) to incur liability?
Normally, the shiur of a kezayit is a function of eating (achilah). If the Torah bypassed the definition of eating by prohibiting a tasteless substance, perhaps any microscopic amount of the nerve should carry the penalty of lashes!
However, the consensus of the Posekim—following the Rambam—is that even if the substance is tasteless, the Torah still couched the prohibition in terms of eating: "Therefore the children of Israel do not eat..." Genesis 32:33.
Thus, while the Torah waived the requirement for flavor, it did not waive the physical requirement for a standard human act of consumption, which requires a kezayit.^Rambam, Hilchot Ma'achalot Assurot 8:1
Psak/Practice
The practical halakhic conclusions of our sugya are codified in the Shulchan Aruch, Yoreh Deah, Chapters 64 and 65, outlining the painstaking process of nikkur (purging/treibering) the hindquarters of kosher animals.
┌────────────────────────────────────────┐
│ Halakhic Status of Gid & Fats │
└───────────────────┬────────────────────┘
│
┌─────────────────────────────┼─────────────────────────────┐
▼ ▼ ▼
┌──────────────────┐ ┌──────────────────┐ ┌──────────────────┐
│ The Main Gid │ │ The Tendrils │ │ The Fat of Gid │
│ (Trunk) │ │ (Kenokanot) │ │ (Chelev Gid) │
├──────────────────┤ ├──────────────────┤ ├──────────────────┤
│ • Biblically │ │ • Rabbinically │ │ • Rabbinically │
│ Forbidden │ │ Forbidden │ │ Forbidden │
│ • Must be │ │ • Must be │ │ • Must be │
│ completely │ │ scraped and │ │ scraped flush │
│ excavated │ │ peeled out │ │ (Hashufi) │
└──────────────────┘ └──────────────────┘ └──────────────────┘
1. The Codification of Gid and Kenokanot
The Shulchan Aruch rules in accordance with the strict view:
גיד הנשה אינו נוהג אלא בבהמה... וחלב שלו מותר מן התורה, אלא שכל ישראל נהגו בו איסור...
"The sciatic nerve applies only to animals... and its fat is permitted by Torah law, but all of Israel have adopted a custom of prohibition..."[^8]
Regarding the kenokanot (the branch fibers):
צריך לנקר הגיד הפנימי שהוא סמוך לעצם, ולחטט אחריו בכל מקום שהוא, ולבטל ממנו כל הקנוקנות שבו...
"One must purge the inner nerve which is adjacent to the bone, and dig after it wherever it is, and nullify/remove all the tendrils that are in it..."[^9]
This requires the menaker (the purger) to not merely shave the nerve flush with the meat, but to actively excavate (meḥatetz) the meat to pull out the white, thread-like branches.
2. The Geopolitics of Hindquarter Consumption
Because the process of nikkur is incredibly complex, requiring expert anatomical knowledge and intensive labor to remove the gid, its kenokanot, the forbidden fats (chelev), and the white kidney fats (shumana de-kulyata), Ashkenazic communities historically adopted a custom to completely sell the hindquarters of animals to non-Jews.
This practice, while not strictly required by the letter of the law, became a protective fence (gezeirah) to avoid any catastrophic errors in the highly technical process of nikkur.
In Sephardic and Middle Eastern communities, however, the art of nikkur remains alive and practiced, with trained menakrim purging the hindquarters in strict accordance with the rulings of Maran Yosef Karo in the Shulchan Aruch.
Takeaway
Our sugya reveals that whether analyzing the celestial choirs of the Ofanim or the physical fibers of the sciatic nerve, the Torah operates on a singular conceptual axis: the sanctification of the physical through the rigorous application of Divine boundaries. Whether through the liturgy of the tongue or the purging of the thigh, we transform the dry "wood" of existence into a vehicle of holiness.
[^1]: Chullin 92a. [^2]: Chullin 92a. [^3]: Chullin 92b. [^4]: Tosafot, Chullin 92a, s.v. Baruch Ofanim הוא דאמרי ליה. [^5]: Kehillot Yaakov on Chullin, Siman 32. [^6]: Chullin 92a. [^7]: Rambam, Mishneh Torah, Hilchot Melachim 9:14. [^8]: Shulchan Aruch, Yoreh Deah 65:1. [^9]: Shulchan Aruch, Yoreh Deah 65:2.
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