Question: Why do some Jews not eat fish with meat, or fish with dairy?
Why do some Jews refrain from eating fish and meat together? Why do other Jews refrain from eating fish and dairy together?
Thank you, Leah
Answer: Dear Leah,
Thank you for you question! Indeed, it is one that many people are uncertain about.
I am posting below excerpts from my book Dalet Amot which I think covers all your questions.
Rabbi Ari Enkin
Although modern-day medicine and science may beg to differ, the sages of the Talmud were under the impression that eating fish and meat together is extremely dangerous to ones health. In fact, in those days, there was actually a dermatological condition which was believed to be caused by eating fish and meat together. As such, the rabbis prohibited the consumption of such mixtures, a practice which continues to this day. This ban applies to fowl as well.
Clearly, however, today this is not the case. Some try to reconcile this medical contradiction, claiming that what was unhealthy in those days may not be in ours. In fact, in talmudic times it was believed that rotten fish was good for you!
It is important to note that this prohibition is unlike the one forbidding mixing milk and meat. Here, it is merely forbidden to eat fish and meat at the exact same time, or in immediate succession. A waiting period, however, is not necessary. The dishes used for eating them may be interchanged, and hence no need for special fish dishes in ones kitchen.
It is interesting to note that some communities are incredibly strict about this practice, and even require the washing of hands between fish and meat courses, as well as the mouth. The washing of the mouth is considered accomplished by merely swishing some fine scotch or other beverage around in ones mouth. Indeed, it is required for individuals to somehow cleanse the mouth in between fish and meat, even by merely eating some other food in between.
Common custom requires one to use a clean or different piece of silverware when switching from fish to meat at the same meal, due to the residue that may remain on the utensil. Both foods, however, may be on the table at the same time.
There are also certain Sephardic and Chassidic communities that prohibit eating fish and milk together (e.g. lox and cream cheese). While this custom is really only an added stringency, fish and milk, too, were at one time considered dangerous to ones health. This is, of course, completely untrue today and all mixtures of fish and milk are permitted, including frying fish in butter.
Again, while there may be measures within Jewish practice that dont seem to have much relevance within todays world of health concerns, let us keep in mind that a danger to life [no matter how small] is even stricter than Torah prohibitions.