The Primary Source for Waiting
The Gemara (Chullin 105a) writes as follows:
“Rav Chisda said: One who eats meat may not eat cheese; [one who eats] cheese may eat meat… Mar Ukva said: Concerning this I am like vinegar, the son of wine. My father, if he would eat meat today, would wait until tomorrow to eat cheese. I, however, will not eat them during the same meal, but at another meal I will eat cheese.”
Whether we follow the practice of Mar Ukva’s father, or that of Mar Ukva himself, the Gemara certainly maintains that one must wait in between eating meat and milk. On the other hand, another Gemara (Chullin 104b) seems to suggest that it is enough to clean and wash out one’s mouth between meat and dairy products (for chicken, the Gemara implies that even this is not required).
Rishonim debate how to resolve this apparent contradiction.
Rabbenu Tam and the Behag (cited by Tosafos 104b) maintain that the Gemaros are referring to two different scenarios. According to these authorities if one cleans out one’s mouth (by eating bread or something similar, and rinsing with water), one may eat cheese immediately after meat. If not, one must wait until the next meal before eating cheese.
However, most Rishonim understand that the idea of cleaning out one’s mouth applies only to eating meat after eating cheese. When eating milk after meat one must wait, and cleaning out one’s mouth does not help.
Tosafos (105a) further write that where the obligation to wait does apply, there is no obligation to wait for a specific length of time, but only to wait until the end of the meal. The Rif (see Beis Yosef 89), the Rosh and the Rambam (Forbidden Foods Chap. 9) explain that Mar Ukva did not mean that one must wait for the next meal, but rather that one must wait the average time between one meal and another. According to the Rambam, this time is “approximately six hours.”
The Shulchan Aruch and Commentaries
The Shulchan Aruch (89:1) rules in accordance with the Rambam: “A person who ate meat, even… fowl, must not eat cheese until he waits six hours.”
The Rema cites the opinions of Rabbeinu Tam and the Behag, according to whom “there is no need to wait six hours, but rather as soon as he clears the table and recites Birkas Ha-mazon he can eat cheese after cleaning out and rinsing his mouth.”
The Rema continues however that “the simple custom in these countries is to wait for one hour, after which one may eat cheese” – adding that waiting for one hour is only effective after Birkas Ha-mazon ( or another brocho achrono) is recited.
The Taz (2) explains that this custom is a form of compromise between the two central opinions: There is no obligation to wait six hours, but on the other hand merely cleaning and rinsing the mouth is not sufficient. One must wait at least one hour.
Yet, the Rema continues: “Some are particular to wait six hours between meat and cheese, and this is the correct practice.” The Taz highlights that “one must chide Bnei Torah and ensure that they do not wait any less than six hours.” The Shach (8) likewise criticizes the lenient customs, and points to the words of the Maharshal who writes, “This (waiting six hours) is proper conduct for anybody who possesses the scent of Torah.”
Although some authorities make a distinction between animal meat and fowl, the Rambam writes that they are equivalent, and this equivalence is ruled by the Shulchan Aruch.
There are likewise authorities who make a distinction between meat itself and a meat dish (or a cheese dish), but the common custom (Rema 89:3) is to treat a meat dish as meat itself, and to wait a full six hours between the dish and dairy foods. However, there is no need to wait after eating parev food cooked in a meaty pot.
The Common Custom
There are places where the custom is to wait three hours between meat and dairy foods (the custom is mentioned by the Darchei Teshuvah 3), and this is the custom of many Jews of German and English origin. A less-well-known custom is to wait an entire day between eating meat and milk, which is based on the Arizal (Darchei Teshuvah 4).
Some wait only one hour, which is the strict halachah according to the Rema. This is known as the Dutch custom.
In the great majority of Jewish communities the regular custom is to wait a full six hours, and those whose families follow this custom should not be lenient in the matter (Peri Megadim, Mishbetzos Zahav 1; Chochmas Adam 40:13).
The Reason for Waiting and its Ramifications
The Rambam writes that the reason for waiting six hours is out of concern that there are pieces of meat left over between a person’s teeth. Even if one cleans out his mouth, we are still apprehensive and only permit him to eat dairy foods after six hours, when from the perspective of the halocho, the meat leftover in his teeth loses its status as meat.
Rashi (Chullin 104b), however, gives a different reason for the halocho, explaining that the meat continues to gives off a taste in a person’s mouth, which lingers until six hours have elapsed.
The Tur (89) explains that the difference between these two explanations differ when a person chewed meat but did not swallow it: According to Rashi there is no reason to wait, since no meat was swallowed, yet according to the Rambam one must wait six hours.
Another ramification is a case where a piece of meat is found in between one’s teeth after six hours: According to the Rambam the meat has lost its status of being called meat and there is no need to remove it, whereas according to Rashi the meat must be removed from the teeth before eating dairy foods.
Rashi will also be stringent in case somebody swallowed meat without chewing it, whereas the Rambam will be lenient, for there is no concern of meat being caught between the teeth.
Practical Rulings
The Tur concludes that it is good to be stringent according to both opinions, and this is also the ruling of the Shulchan Aruch. For this reason, the Rema (89:1) writes that if meat is found between teeth after six hours, one should be careful to remove it.
In spite of the above, we find the Rabbi Akiva Eiger (89:2) rules leniently concerning somebody who chewed meat without swallowing it, deriving from the Rema that one does not have to wait after chewing alone. Some authorities dispute this ruling and argue that one must wait after chewing alone (Peri Megadim 1; Gilyon Maharshak).
However, where neither reason for waiting six hours applies, there is no need for stringency. Therefore, somebody who merely tastes meat, without chewing or swallowing it, does not need to wait at all, and authorities dispute whether he even needs to wash out his mouth (see Pe’as Ha-Shulchan 20; Badei Ha-Shulchan 16).
In a similar application, Rav Moshe Feinstein (Iggros Moshe, Yoreh De’ah 2:26) writes that there is no need to wait six hours after swallowing a meaty pill, because both reasons are not applicable (he proceeds to write that because the halachah doesn’t apply to the pill, it will remain true even if the pill is chewed).
Yet, Sefer Ha-Kashrus (no. 46) cites Rav Moshe that the pill should nonetheless not actually be swallowed together with milk.
Cases of Doubt
A person often has a doubt as to whether six hours have elapsed, and the question is how a case of safek should be treated.
The Yad Yehudah (beginning of no. 89) writes that one must act stringently when in doubt, because although no Torah prohibition is involved, it is a davar she-yeish lo matirin (something that can eventually be done in a totally permitted manner – by waiting until six hours certainly elapsed), so that the doubt cannot be used to permit eating.
However, some are lenient in this matter, based on the ruling of the Rema whereby according to the strict halachah one hour is enough (Badei Ha-Shulchan).
Moreover, one can also adduce the wording of the Rambam, who rules that a person must wait “approximately six hours.” Based on this wording some authorities write that one can eat dairy foods after five-and-a-half hours, and there is no need wait the full six hours (Orchos Chaim Vol. 2, p. 335; Kol Bo no. 106). The Meiri actually writes that one must wait “five or six hours.”
The Young and the Sick
It is permitted for the sick to eat dairy products before six hours are up, if these products are important for them. It is best to wait at least an hour, and to recite Birkas Ha-mazon before eating dairy foods (Pischei Teshuvah 3, citing from Chasam Sofer 73; the Chochmas Adam 40:13 writes that this is permitted even for somebody who is only slightly ill). The same halachah will apply to a lady in the first month after giving birth.
A young child (under the age of three) does not need to wait at all after meat, and a child under the age of nine need not wait more than one hour, which is the principle halachah according to the Rema (Chelkas Yaakov 2:88, 3:147; Shevet Halevi 4:84). For a child over the age of nine, one can still be lenient, if the child requires milk, after an hour has elapsed.
It is a fairly common custom to train children from the age of six or seven to wait six hours where this is possible. Rabbi Moshe Sternbuch (Teshuvos Ve-Hanhagos 1:435) writes that a child over the age of six or seven should wait three hours, whereas a child over the age of nine or ten should wait the full six hours.
