The mixture of meat and dairy () is forbidden according to Jewish law. This dietary law, basic to kashrut, is based on two verses in the Book of Exodus, which forbid "boiling a (goat) kid in its mother's milk"; and a third repetition of this prohibition in Deuteronomy.
Explanations for the law The rabbis of the Talmud gave no reason for the prohibition.Pesahim 44bHullin 108a Later authorities, such as Maimonides, opined that the law was connected to a prohibition of idolatry in Judaism.Maimonides, Moreh, 3:48 Obadiah Sforno and Solomon Luntschitz, rabbinic commentators living in the late Middle Ages, both suggested that the law referred to a specific Canaanite religious practice, in which young goats were cooked in their own mothers' milk, aiming to obtain supernatural assistance to increase the yield of their flocks.Solomon Ephraim Luntschitz, Keli Yakar, to Exodus 23:19Obadiah ben Jacob Sforno, commentary, to Deuteronomy 14:21 More recently, a theogonous text named the birth of the gracious gods, found during the rediscovery of Ugarit, has been interpreted as saying that a Levantine ritual to ensure agricultural fertility involved the cooking of a young goat in its mother's milk, followed by the mixture being sprinkled upon the fields.Peake's commentary on the BibleWycliffe Bible Commentary Still more recent sources argue that this translation is incorrect.
Some rabbinic commentators saw the law as having an ethical aspect. Rashbam argued that using the milk of an animal to cook its offspring was inhumane, based on a principle similar to that of Shiluach haken.Rashbam to Exodus 23:19, quoting and Chaim ibn Attar compared the practice of cooking animals in their mother's milk to the slaying of nursing infants.Chaim ibn Attar, commentary to Exodus 23:19
The Torah law as understood by the rabbis Three distinct laws The Talmudic rabbis believed that the biblical text only forbade cooking a mixture of milk and meat, but because the biblical regulation is triplicated they imposed three distinct regulations to represent it: not cooking meat and milk together (regardless of whether the result was eaten) not eating milk and meat together (regardless of whether it was cooked together) not benefiting from the mixture in any other way
Jacob ben Asher, an influential medieval rabbi, said that the gematria of do not boil a kid (Hebrew: ) is identical to that of it is the prohibition of eating, cooking and deriving benefit (Hebrew: ), a detail that he considered highly significant.Jacob ben Asher, commentary on Deuteronomy 14:24 Deriving benefit was later interpreted by medieval writers to include: Serving mixtures of milk and meat in a restaurant, even if the clientele are non-Jewish, and the restaurant is not intended to comply with kashrut Feeding a pet with food containing mixtures of milk and meatAbraham Danzig, Wisdom of Man 40:62 Obtaining a refund for an accidental purchase of mixtures of milk and meat, as a refund constitutes a form of saleJacob ben Asher, Hoshen Mishpat 234:4
The classical rabbis only considered milk and meat cooked together biblically forbidden. Jewish writers of the Middle Ages also forbade consumption of anything merely containing the mixed tastes of milk and meat.Jacob ben Asher, Yoreh De'ah 87:1 This included, for example, meat that had been soaked in milk for an extended period.Hezekiah da Silva, Peri Hadash 87:2 The prohibition against deriving benefit was seen as being more nuanced, with several early modern authorities (including Moses IsserlesRema 87:1 and David HaLevi SegalTaz, Yoreh De'ah 87:1) said that this restriction only applied to the milk and meat of g'di, not to the much wider range of milks and meats prohibited by the rabbis; other prominent medieval rabbis, like Solomon Luria, disagreed, believing that the prohibition of deriving benefit referred to mixtures of all meats and milks.cf. Dagul Mervava 87:1 re Rambam's opinion
The term "gedi" The Book of Genesis refers to young goats by the Hebrew phrase (), but the prohibition against boiling a kid... only uses the term gəḏî (גדי). Rashi, one of the most prominent talmudic commentators, argued that the term gəḏî must actually have a more general meaning, including calves and lambs, in addition to young goats.Rashi, commentary, to Exodus 23:19 Rashi also argued that the meaning of is still narrow enough to exclude birds, all the undomesticated kosher animals (for example, chevrotains and antelope), and all of the non-kosher animals.Rashi, commentary, to Deuteronomy 14:21 The Talmudic writers had a similar analysis,Hullin 8:7 but believed that since domesticated kosher animals (sheep, goats, and cattle) have similar meat to birds and to the non-domestic kosher land-animals, they should prohibit these latter meats too,Hullin 113a creating a general prohibition against mixing milk and meat from any kosher animal, excepting fish.Hullin 115b
Consumption of non-kosher animals (e.g., pigs, camels, and turtles) is prohibited in general, and questions about the status of mixtures involving their meat and milk would be somewhat academic. Nevertheless, the lack of a classical decision about milk and meat of non-kosher animals gave rise to argument in the late Middle Ages. Some, such as Yoel Sirkis and Joshua Falk, argued that mixing milk and meat from non-kosher animals should be prohibited,Yoel Sirkis, Bayit ChadashJoshua Falk, Derishah 87 but others, like Shabbatai ben Meir and David HaLevi Segal, argued that, excluding the general ban on non-kosher animals, such mixtures should not be prohibited.Shabbatai ben Meir, Lips of the Priest 3David HaLevi Segal, Rows of Gold 2
The term "halev immo"
Rashi expressed the opinion that the reference to mother's milk must exclude fowl from the regulation, since only mammals produce milk.Rashi, commentary to Exodus 34:26 According to Shabbethai Bass, Rashi was expressing the opinion that the reference to a mother was only present to ensure that birds were clearly excluded from the prohibition;Shabbethai Bass, Sifsei Chachamim to Rashi, commentary to Exodus 34:26 Bass argued that Rashi regarded the ban on boiling meat in its mother's milk to really be a more general ban on boiling meat in milk, regardless of the relationship between the source of the meat and that of the milk.
Substances derived from milk, such as cheese and whey, have traditionally been considered to fall under the prohibition,Hullin 105aJacob ben Asher, Yoreh De'ah 87:8 but milk substitutes, created from non-dairy sources, do not. However, the classical rabbis were worried that Jews using artificial milk might be misinterpreted, so they insisted that the milk be clearly marked to indicate its source. In the classical era, the main form of artificial milk was almond milk, so the classical rabbis imposed the rule that almonds must be placed around such milk; in the Middle Ages, there was some debate about whether this had to be done during cooking as well as eating,Moses Isserles, Sifsei De'ah 7 or whether it was sufficient to merely do this during the meal.Shabbatai ben Meir, Lips of the Priest 7
The term "bishul"
Although the biblical regulation literally only mentions boiling (Hebrew: ,), there were questions raised in the late Middle Ages about whether this should instead be translated as cooking, and hence be interpreted as a reference to activities like broiling, baking, roasting, and frying. Lenient figures like Jacob of Lissa and Chaim ibn Attar argued that such a prohibition would only be a rabbinic addition, and not the biblical intent,Jacob of Lissa, Havaat Da'at 1Chaim ibn Attar, Beautiful Fruit 3 but others like Abraham Danzig and Hezekiah da Silva argued that the biblical term itself had this wider meaning.Hezekiah da Silva, Peri Hadash 87:2Abraham Danzig, Wisdom of Man 40:1
Though radiative cooking of meat with dairy produce is not listed by the classical rabbis as being among the biblically prohibited forms of cooking such mixtures, a controversy remains about using a microwave oven to cook these mixtures.
Rabbinic additions to the Biblical law The classical rabbis interpreted to mean that they should (metaphorically) create a protective fence around the biblical laws, and this was one of the three principal teachings of the Great Assembly.Pirkei Avot 1:1 Mixing of milk and meat is one area of halacha where a particularly large number of "fences" have been added. Nevertheless, the rabbis of the classical and Middle Ages also introduced a number of leniencies.
Minuscule quantities The classical rabbis expressed the opinion that each of the food rules could be waived if the portion of food violating the regulations was less than a certain size, known as a (), unless it was still possible to taste or smell it;Yoma 73bYoma 80a for the "milk and meat" regulations, this minimal size was a (), literally meaning anything "similar to an olive" in size.Joseph Babad, Minchat Chinuch 92 However, the is merely the minimum amount that leads to formal punishment in the classical era, but even "half a is prohibited by the Torah".
Many rabbis followed the premise that "taste is principal" (, ): in the event of an accidental mixing of milk and meat, the food could be eaten if there was no detectable change in taste. Others argued that forbidden ingredients could constitute up to half of the mixture before being disallowed.Shabbatai ben Meir, Lips of the priest 109:6Abraham Danzig, Wisdom of Man 51:4 Today the rabbis apply the principle of Abraham Cohen Pimentel, Minhat Kohen 2:1:2-6, giving an overview of the various opinions of Rashi, Maimonides, and Nissim of Gerona ('nullified in sixty'), that is, permissible so long as forbidden ingredients constitute no more than of the whole.Binyomin Forst, The Laws of Kashrus, Mesorah Publications, Ltd. 2000, page 53
Due to the premise that "taste is principal", (i.e., 'neutral') foods are considered to take on the same "meat/dairy produce" classification as anything they are cooked with.Jacob Sofer Kaf haChaim 89:52–53
Physical proximity Prominent rabbis of the Middle Ages insisted that milk should not be placed on a table where people are eating meat, to avoid accidentally consuming milk while eating meat, and vice versa.Jacob ben Asher, Yoreh De'ah 88:1Shabbatai ben Meir, Lips of the priest Tzvi Hirsch Spira, an early 20th-century rabbi, argued that when this rule was created, the tables commonly in use were only large enough for one individual;Tzvi Hirsch Spira, Darhei Teshuva 7, quoting Chaim Benveniste's Kenesset HaGedolah Spira concludes that the rule would not apply if the table being used was large, and the milk was out of reach of the person eating meat (and vice versa).Tzvi Hirsch Spira, Darhei Teshuva 7
The rabbis of the Middle Ages discussed the issue of people eating milk and meat at the same table. Jacob ben Asher suggested that each individual should eat from different tablecloths,Jacob ben Asher, Yoreh De'ah 88:2 while Moses Isserles argued that a large and obviously unusual item should be placed between the individuals, as a reminder to avoid sharing the foods.Moses Isserles, The Tablecloth 88:2 Later rabbinic writers pointed out exceptions to the rule. Chaim ibn Attar, an 18th-century kabbalist, ruled that sitting at the same table as a non-Jew eating non-kosher food was permissible;Chaim ibn Attar, Beautiful Fruit 1 Yechiel Michel Epstein, a 19th-century rabbi, argued that the risk was sufficiently reduced if individuals sat far enough apart that the only way to share food was to leave the table.Yechiel Michel Epstein, Laying the table 88:8
Classification of foods To prevent the consumption of forbidden mixtures, foods are divided into three categories.see for example, Aharon Pfeuffer Kitzur Halachot Basar B'Chalav "meat" (North America) or "meaty" (UK) (; ) "dairy" (North America) or "milky" (UK) (; ) (or , ; from the Yiddish word , , meaning 'neutral')