The Shulchan Aruch teaches that we are required to wait between eating meat and milk.

According to the Sephardim, it is the halakhah which defines the waiting period as six hours. According to the Ashkenazim, the length of time required depends on the local custom. However, it is recommended to wait six hours.

The source for this halakhah and disagreement between the Ashkenazim and Sephardim is in a Gemara in Chulin. The Gemara first teaches that one is not permitted to eat dairy products, if he still has meat within his teeth. As we can see in our Parasha, the Torah associates the meat between teeth as a stage in eating the meat. 'הַבָּשָׂר, עוֹדֶנּוּ בֵּין שִׁנֵּיהֶם' - ‘While the flesh was yet between their teeth’ (Numbers 11:33)

The Gemara then gives a definition of how long we are to wait for: "Mar ‘Ukba said: In this matter I am as vinegar is to wine compared with my father. For if my father were to eat flesh now he would not eat cheese until this very hour tomorrow, whereas I do not eat [cheese] in the same meal but I do eat it in my next meal". Mar Ukba's father would wait 24 hours between meat and milk.

There is only one community in the entire Jewish world that we know which actually followed Mar Ukba's father, and that is the Ethiopian community. The rest of Am Yisrael hold by Mar Ukba himself. Yet, Mar Ukba did not actually give us a time definition. How long does it take between one meal and the other? Was he merely referring to however long it takes to wrap up one meal and begin another, or to the length of time between meals?

The Sephardim interpreted this teaching according to the latter and calculated that it takes six hour between one meal and the other (there are obviously a few more considerations such as how long it takes for the meat in the teeth to dissolve). The Ashkenazim follow the former, and thus after a few required measurements it is possible that Mar Ukba would sit down for a dairy meal.

This, however, is where the fascinating concept of the power of the custom comes into account. The Custom of all communities is to wait a more lengthy amount of time than the minimum given by Mar Ukba, some wait an hour, some three or four, and most, probably wait six.

There are two forms of Customs, those which were enforced by Chazal (which possibly have the status of a Mitzvah from the Torah "you shall not turn aside from the sentence which they shall declare") and those which the people took upon themselves.


Rav Kook writes that any Custom which the nation adopts is revealing yet another layer of how devoted they are to God.
Each form of Custom obliges us no less than halakhah. Though it is true that when in doubt or in need, there is more place for leniency regarding Customs which the people took upon themselves. There is a fascinating idea behind the power behind Customs. Once the nation adopted a Custom each individual is obliged to keep it.

According to Rav Hai Gaon, our obligation to accept any halakhah is through the power invested in the nation. It is the nation which chooses what we follow. If the nation chose a Custom, we are all obliged to keep it.

Rav Kook writes that any Custom which the nation adopts is revealing yet another layer of how devoted they are to God. We should therefore cherish our customs and keep them to the finest detail.

The Vilna Gaon once addressed our Gemara and taught something very profound. Though one must continue the Customs of his parents, this is not the case when they were practicing something which they took upon themselves.

So  Mar Ukba was not obliged to wait 24 hours like his father. Furthermore, Mar Ukba himself tells us that he is like vinegar to wine in comparison to his father. Essentially, according to the Vilna Gaon, Mar Ukba is telling us that we should always be aware of what level we are on.

One should not attempt to jump stages in his worship of God, but rather build up gradually to ensure that he remain stable and does not fall.