Eruvin 83

Portion control.

Anyone who’s ever been on a diet, worked as a chef or a server, or organized a home kitchen knows that portion control is key to managing food intake and supply. Today’s daf looks at this topic in the context of — what else? — an eruv.

The mishnah on the bottom of 82b asks a logical question: what is the quantity of food needed to make an eruv techumin (an eruv established for the purpose of extending the Shabbat boundary)? We know that it’s supposed to be enough for two meals, but how much is that exactly? Are we talking about Shabbat meals or weekday meals? Do we assume that people eat more on Shabbat when they are relaxing and have more time to eat, or on weekdays when they are working and need the energy for physical labor? And what exactly is the measurable quantity of those meals? Do those measurements differ according to location? And how much should all this cost?

After a detailed discussion about the matters enumerated above, the Gemara on 83b turns its attention to portion control.

The Torah states that the manna, the dough of the wilderness, was “an omer (about two liters) a head” (Exodus 16:16).

From here the sages also said: One who eats roughly this amount each day is healthy as he is able to eat a proper meal; and he is also blessed, as he is not a glutton who requires more. One who eats more than this is a glutton, while one who eats less than this has damaged bowels and must see to his health.

Rashi, commenting on our passage, notes that a person eating the right quantity is healthy because he has eaten sufficiently, and he is blessed because he isn’t a glutton, of whom it is said “The stomach of the evil shall suffer want.” (Proverbs 13:25)

Rabbi Adin Steinzaltz further stated that a person is blessed when he has what he needs in order to satisfy his hunger. One who eats more than he needs will feel ill afterwards, because there will be too much food in his stomach to digest. (Thanksgiving dinner, anyone?)

The sage and physician Maimonides, writing over 800 years ago, devoted lots of ink to proper eating habits. According to his view:

“One should not eat until his stomach is full. Rather, he should stop eating when he has eaten close to three quarters of his full

satisfaction… Overeating is like poison to anyone’s body. It is the main source of all illness. Most illnesses which afflict a man are caused by harmful foods or by his filling his stomach and overeating, even of healthful foods. This was implied by King Solomon in his wisdom: ‘Whoever guards his mouth and his tongue, guards his soul from distress.’ (Proverbs 21:23) ‘Guards his mouth,’ from eating harmful food or overeating and guards ‘his tongue’ from speaking about things other than his needs.” (Hilchot De’ot 4:2)

So, how much is too much? It seems that our sages, like home and commercial cooks today, not to mention the diet industry, believe that enough is just that … enough. To be healthy, we should eat what we need, and no more. By extension, creating an eruv techumin shouldn’t bankrupt us, and should contain just enough for our needs.

The words of Birkat Hamazon, the traditional grace after meals which we studied extensively in tractate Berakhot, provides the perfect conclusion to this topic:

“When you have eaten your fill, give thanks to the Lord your God for the good land which God has given you. Blessed is Adonai for the land and its produce.”

Read all of Eruvin 83 on Sefaria.

This piece originally appeared in a My Jewish Learning Daf Yomi email newsletter sent on October 31st, 2020. If you are interested in receiving the newsletter, sign up here.

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