Maternal Instincts, Woolly Firstborns, and Unintended Plucking

How Tosafot resolves subtle textual details concerning nursing mothers, shearing prohibitions, and unintentional labor on Festivals.

Recognizing Offspring in the Dark

A male בכור (firstborn) animal belongs to the kohen and cannot be used for ordinary work or meat. If several mothers give birth together, we must determine which mother gave birth to which offspring. A baraita states that if an owner enters his flock at night and sees mothers delivering, and the next morning finds males nursing from previously birthed mothers and females from first-time mothers, he need not suspect a mix-up.

Rashi explains that this avoids treating the males as a ספק בכור (doubtful firstborn). Tosafot asks why the baraita added the narrative detail of entering at night and waking in the morning. Surely it could have simply stated that one observed males and females nursing from these respective mothers!

Tosafot answers that this specific wording teaches an important novel principle. Even though the births occurred in darkness when mothers do not yet recognize offspring and readily make mistakes, we still do not suspect a mix-up.

דאע"ג דודאי היתה תחלת לידתן בלילה שעדיין אין האמהות מכירין בוולדותיהן ודרכן לטעות בלילה ובא לו בנה של זו אצל זו אפי' הכי לא חיישינן

Even though the start of their birth was certainly at night, when the mothers do not yet recognize their offspring and it is their way to err at night such that the offspring of this one comes to that one, even so we are not concerned. (Tosafot on Bekhorot 24a:5:1)

Clearing Wool with a Cleaver

The Torah strictly forbids shearing a בכור. When slaughtering a blemished firstborn, Rabbi Yosei ben HaMeshullam permits clearing space in the wool with a קופיץ (cleaver), plucking hair without moving it away. Rashi explains that one makes space for the knife to prevent חלדה (concealment of the blade under wool).

Tosafot rejects Rashi's explanation, noting that if חלדה were the concern, a knife is far more vulnerable to concealment than a wide cleaver. Furthermore, a cleaver is blunt and clumsy, requiring a wide path cleared in the wool to slice cleanly.

Tosafot also asks why the Mishnah specifically mentions a בכור rather than ordinary sacrifices. Because an owner holds a firstborn for months awaiting a permanent blemish, it develops unusually long and tangled wool that obstructs slaughter.

ונראה לפרש דנקט הכא קופיץ משום דבעי עשיית מקום טפי מסכין וצריכה עשיית מקום גדול

And it appears correct to explain that it mentions a cleaver here because it requires making space more than a knife, and requires a large space to be made. (Tosafot on Bekhorot 24b:5:1)

Unintentional Labor on a Festival

The Gemara asks whether clearing space with a cleaver is also permitted when slaughtering on Yom Tov (Festival). The dilemma hinges on why Rabbi Yosei ben HaMeshullam permits it on a firstborn: is plucking fundamentally distinct from shearing, or is it permitted as a דבר שאינו מתכוין (unintentional act)?

Tosafot is troubled by this formulation. If the act is intentional, it is clearly forbidden on Yom Tov, and if unintentional, it should obviously be permitted. Why then does the Gemara frame the doubt around unintentional action?

Tosafot explains that even if plucking is not biblical shearing, intentionally plucking hair remains rabbinically prohibited. The inquiry on Yom Tov is whether an unintentional action is permitted where a Torah prohibition is at stake—namely, uprooting a growing thing—or only where the underlying concern is merely rabbinic.

Tosafot shows that precise legal phrasing often protects against real-world hurdles, from nighttime confusion among ewes to tangled wool and Sabbath labor.

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