ויקרא, פרק כ״ב, פסוק כ״ח

When taking the life of an animal for food or sacrifice, God places specific limits designed to instill mercy in the human heart and distance people from cruelty [שד״ל, רש״ר הירש, בכור שור]. This law elevates the natural maternal instinct of the animal to a moral ideal. It also sharply distinguishes the Israelite approach to sacrifices from pagan beliefs, which viewed sacrifices merely as acts of destruction meant to appease a deity [רש״ר הירש]. The restriction applies universally, governing both sacred offerings and everyday meat [רלב״ג, בכור שור, רש״ר הירש]. It encompasses domesticated livestock from the moment of birth [מלבי״ם, הכתב והקבלה], including mixed breeds [רלב״ג, תורה תמימה], but excludes wild animals and birds [חזקוני, תורה תמימה, אדרת אליהו].

While the commandment is framed in masculine terms, the primary approach among commentators is that it fundamentally applies to a mother and her offspring, whether that offspring is male or female [רש״י, רמב״ן, טור, מזרחי]. This is because an animal naturally bonds with its mother rather than its father [מזרחי, גור אריה]. The masculine phrasing simply continues the style of the preceding laws regarding sacrifices, utilizing general species names that can also refer to females [רמב״ן, רבנו בחיי, גור אריה]. Regarding a father and his offspring, Jewish law generally assumes paternity is unknown in the animal kingdom, meaning there is no formal punishment for slaughtering them on the same day. However, many commentators stress that if the identity of the father is known with certainty, slaughtering both remains strictly forbidden [תורה תמימה, חזקוני, הכתב והקבלה, פרדס יוסף]. Furthermore, there is a view that the restriction applies equally to both males and females without distinction [אבן עזרא].

The law is structured to cover various scenarios involving multiple people and specific methods. If one person slaughters the mother and a second person slaughters the offspring, the second individual violates the prohibition and faces the penalty [מזרחי, תורה תמימה, מלבי״ם]. The sequence of events is irrelevant; the restriction is violated regardless of whether the mother or the young is killed first [רש״י, מזרחי]. Furthermore, the prohibition applies exclusively to a valid, kosher slaughter that renders the animal fit for consumption. Killing the animal through other methods, such as stabbing or sterilization, does not fall under this specific restriction [תורה תמימה, רש״ר הירש, אדרת אליהו].

The timeframe for this restriction spans a single day, calculated from evening to the following nightfall, mirroring the cycle of creation [תורה תמימה, ביאור יש״ר]. To prevent accidental violations during periods of high demand for meat, the Sages instituted a safeguard during four key times of the year: the eves of Sukkot, Passover, Shavuot, and Rosh Hashanah. On these days, a seller is obligated to inform the buyer if the animal's mother or offspring was already sold that same day [תורה תמימה, העמק דבר]. In modern times, agricultural practices have drastically changed. Because adult cows and young calves are typically raised and sent to processing facilities at entirely different times, the statistical likelihood of encountering a mother and her offspring on the same day is exceptionally low, significantly reducing the practical concern of this prohibition today [ברכת אשר].