Too much or too little bread is not good. So what is the correct amount? TB Eruvin 83

Today’s daf TB Eruvin 83 is another one made for math lovers. In the Mishnah on the preceding page Rabbi Yoḥanan ben Beroka and Rabbi Shimon disagree on the amount of bread constitutes two meals. Rabbi Yoḥanan ben Beroka holds that ½ kav equals 1/12 se’a. Two meals equals ½ kav or four meals per kav. Rabbi Shimon holds that 1 kav equals three meals. Two meals equals 2/3 loaves of bread or 2/9 kav. To complicate matters the size of a se’a changed. The se’a midbarit (dough of the wilderness- דְּמִדְבָּרִית), the measurement determined by Moses in the desert, equalled 144 egg bulks. The se’a yerushalmit (דִּירוּשַׁלְמִית), the measurement used when the Second Temple stood, equalled 6/5 se’a midbarit or 173 egg bulks. Se’a Tziporit (דְּצִיפּוֹרִית), the measurement used when the center of Rabbinical moved to Tzipori where Rabbi Yehuda HaNasi lived, equalled 6/5 se’a yerushalmit or 207 egg bulks. Math lovers check out all their caculations!

With this introduction, we can better understand the laws of separating ḥalla from the dough. This ḥalla portion was given to the kohnim. The question arises what is the minimum amount of dough that requires a person to separate ḥalla.

“Our Sages taught a baraita: The verse states: “You shall set apart a cake of the first of your dough as a gift; like the gift of the threshing floor, so shall you set it apart” (Numbers 15:20). What is the quantity of dough from which ḥalla must be separated? The amount of “your dough.” And how much is “your dough”? This amount is left unspecified by the verse. The Gemara answers: It is as the amount of the dough of the wilderness. The Gemara again asks: And how much is the dough of the wilderness? The Gemara responds: The Torah states that the manna, the dough of the wilderness, was “an omer a head” (Exodus 16:16). A later verse elaborates on that measure, as it is written: “And an omer is the tenth part of an eifa” (Exodus 16:36). An eifa is three se’a, which are eighteen kav or seventy-two log. An omer is one-tenth of this measure. From here, this calculation, Sages said that dough prepared from seven quarters of a kav of flour and more is obligated in ḥalla. This is equal to six quarter-kav of the Jerusalem measure, which is five quarter-kav of the Tzippori measure.

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.” (Sefaria.org translation)

We still separate ḥalla from our dough today. Because the Temple no longer stands and all the kohanim are ritually unready, they are not permitted to eat this gift of ḥalla. We may not eat it either since we are not kohanim, Consequently, we remove a symbolic piece of dough and burn it so it is no longer edible.

One needs to separate the ḥalla if the dough equals 3.86 lbs (1.75 kilo or more than 15 cups) with a blessing “Blessed are You, Lord our God, Ruler of the Universe, who has sanctified us with commandments, and commanded us to separate ḥalla.” Hold the piece of dough and say “harei zo cḥalla” (This is ḥalla). One still needs to separate the ḥalla from the dough is more than 2.76 lbs (1.25 kilo or 10-14 cups), but without a blessing. One does not need to separate ḥalla is less than 2.76 lbs. See Shulkhan Arukh, Yoeh deah, 324:1