Defining Permanent Blemishes in Animals and Priests

Tosafot examines what constitutes a biblical blemish and why criteria differ between animals, slaves, and priests.

Deriving the Definition of a Blemish

A firstborn animal is sacred from birth and may only be slaughtered for non-sacred consumption if it sustains a permanent blemish. The Torah lists specific defects—lameness and blindness—bracketed by general references to blemishes. Applying the hermeneutical rule of כלל ופרט וכלל (a generalization, a detail, and a generalization), the Gemara deduces that any defect resembling the detail qualifies.

The Gemara concludes that this derivation includes all מומין שבגלוי ואינן חוזרין (blemishes that are exposed and do not regenerate). Under this biblical rule, any obvious and irreversible defect permits slaughtering a firstborn outside the Temple.

מָה הַפְּרָט מְפוֹרָשׁ — מוּמִין שֶׁבַּגָּלוּי וְאֵינָן חוֹזְרִין, אַף כֹּל מוּמִין שֶׁבַּגָּלוּי וְאֵינָן חוֹזְרִין.

Just as the items mentioned in the detail are clearly defined as blemishes that are exposed and do not regenerate, so too, all blemishes that are exposed and do not regenerate [are included]. (Bekhorot 37a:18)

Why Missing Teeth Are Not Blemishes

Tosafot raises a difficulty based on this definition. The loss of a tooth is an exposed defect that does not grow back, and knocking out a tooth frees a Canaanite slave. Yet later in the tractate, missing teeth do not disqualify an animal, nor do they disqualify a human priest except for appearance.

Tosafot answers that teeth naturally fall out due to old age, making them unlike lameness or blindness. By contrast, a slave goes free because Scripture explicitly revealed that he goes free through a minor injury. Similarly, deafness disqualifies a priest only because he is אינו שוה בזרעו של אהרן (not physically uniform with Aaron's descendants), while a deaf animal remains kosher for sacrifice.

וא"ת ומ"ט לא הוי הכא מומא כשנפלה שינו כיון דחשיב מום שבגלוי ואינו חוזר

And if you say: What is the reason that here it is not considered a blemish when its tooth falls out, given that it is deemed an exposed blemish that does not regenerate? (Tosafot on Bekhorot 37a:18:1)

Slaughtering Versus Disqualifying an Offering

The Gemara later addresses a piercing in the ear of an animal. Rabbi Yosei son of Rabbi Yehuda rules that a hole must be the size of a lentil to allow slaughter. Yet regarding a Hebrew slave whose ear is pierced, Rabbi Yosei permits using a needle, and the Sages state that a priest cannot undergo this piercing because it inflicts a blemish.

To resolve this, Rav Chana bar Ketina distinguishes between slaughtering an animal and disqualifying a sacrifice. Rashi explains that many defects disqualify an animal from the altar without permitting it to be slaughtered for personal use.

The Discrepancy of a Needle Piercing

Tosafot questions this resolution. If a needle prick creates an authentic biblical blemish that disqualifies a priest, why is a lentil-sized hole required to permit slaughtering a firstborn?

Tosafot offers three answers. First, slaughtering for a minute hole was rabbinically forbidden lest people mistakenly permit hidden blemishes. Second, a minute piercing is not an objective blemish, but disqualifies a priest because he is אינו שוה בזרעו של אהרן (not physically uniform with Aaron's descendants). Third, a needle puncture might be a מום עובר (temporary blemish) that heals, yet a priest cannot be subjected to even a temporary disqualification.

An animal must have a conspicuous, permanent blemish to be slaughtered, whereas minor or temporary flaws may still disqualify a priest from service.

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