In the Hebrew the numbers 5774 are expressed as Tof shin ayin dalet. One could understand these letters as an abbreviation for the expression, “Tehye Shnas Dalet Eiruvin” it will be a year in which four Eruv Tavshilins will be made.”
What is an Eruv Tavshilin?
Whenever Yom Tov comes immediately before Shabbos, in other words, on a Friday – an Eruv Tavshilin must be made. An Eruv Tavshilim is a Rabbinic device that allows one to “continue preparing and cooking” for Shabbos on Yom Tov. In other words, through the Eruv Tavshilin, one actually begins the Shabbos preparations on the day before Yom Tov. The Malachos performed on the Yom Tov for Shabbos are considered to be a continuation of these preparations. (Rema O.C. 527:1)
We learned, however, that performing Malacha on a Yom Tov for another day other than the Yom Tov itself is, in fact, a Torah prohibition. If this is the case, then how could it be that a Rabbinical enactment allows one to get around a Biblical prohibition?
The answer is that, technically, it was permitted by the Torah to cook on Yom Tov for Shabbos.
Why was it permitted? There is an argument about this very point that is found in the Gemara. Rabbah said that it was permitted because “you never know when guests may drop in and eat.” Rav Chisda, on the other hand, said that the Torah actually made an exception for Shabbos.
The Rabbis, however, forbade cooking on Yom Tov even when it was done for Shabbos. Why did they forbid it?
Either because they were afraid that people would take the best items for Yom Tov and leave nothing significant for Shabbos (Rabbah’s explanation). Or because they were afraid that it would lead to much confusion in that people would think that one could also cook for another day of the week, too, not just Shabbos (Rav Chisda’s explanation).
DIFFERENCE IN HALACHA
There is a difference between the two approaches. According to Rabbah, all the food would have to be cooked before Shabbos. According to Rav Chisda, the food may still be cooking over Shabbos. According to whom do we pasken? Ideally, we should be concerned to make sure the food is all cooked from before Shabbos starts. Post fact, we can rely on the opinion of Rav Chisda.
According to both opinions, however, the cooking and baking that is permitted for Shabbos may only be done on Friday. It may not be done on Thursday at all.
If guests are expected who are not supported financially by the person performing the Eruv Tavshilim, then in order for the guests to avail themselves of the Eruv Tavshilin, the host must give a portion of it to someone else who will accept upon the behalf of the guests. According to the Shulchan Aruch (527:10), he cannot accept it for them, and he requires another person (a spouse is fine). This accepting on behalf of the guests is called “Zikui.”
Most Poskim are of the opinion that when a married son comes to the home of his parents, the Zikui system should be used rather than mere reliance on the Eruv performed by the household owner.
To perform the Zikui one merely has to say to another, “please accept this on behalf of those who are coming earlier.”
If one inadvertently omitted the cooked food, the egg in our case, the Eruv Tavshilin must be made again. The Eruv may not be used at all – even if it is just for baking. However, if one inadvertently left out the challah or the matzah, the Eruv Tavshilin is valid.
If one ate or lost the egg or cooked item before Shabbos began then the Eruv is not valid. If one ate or lost the baked item before Shabbos then the Eruv is still valid.
Ideally, both the baked item and the cooked item should be the size of one Baitza, but b’dieved it is valid if it was only the size of a k’zayis.
Ideally, one should also cook the food for the purpose of the Eruv Tavshilin. Although most people have the custom to use an egg, the Mishna Brurah (527:8) recommends that one should use meat or fish on account of the notion of Hidur Mitzvah – beautifying a Mitzvah. The Aruch HaShulchan explains that the hard-boiled egg was used because it spoiled less than fish or meat.
Even if someone does not plan on cooking or baking for the Yom Tov, he or she should still make an Eruv Tavshilin. This is in order to permit the lighting of the Shabbos candles on Yom Tov (See SA 527:19). However, if one is not cooking and or baking, a berachah would not be recited under such circumstances. If the person changes his or her mind and does participate in cooking or baking activities, then it is permitted to do so even if the berachah was not recited (See SSK 31 note 83 citing Rav Shlomo Zalman Auerbach).
The Rav of each town also makes an Eruv Tavshilim for people in his town who neglected to make one. However, one is only permitted to rely on the Rav’s Eruv one time. There is a question as to whether this means once in a lifetime or one time per year.
We set aside food for the Eruv Tavshilin from before Yom Tov. These foods should be eaten on Shabbos. At a minimum one must have one cooked item (and at least a k’zayis of it) and ideally, one baked item as well. The custom is to use an egg and a matzah or a challah. It is proper to use these foods at the Shabbos meal. Some, including the Mishna Brurah, recommend using meat or fish instead of an egg as the cooked item.
Generally, a berachah is recited on the Eruv and the text for the Eruv is recited. It is in Aramaic. If the person performing the Eruv understands Aramaic, then there is no need to recite it in Hebrew or in English. If not, then it should be recited in English. The words mean: With this Eruv, we are permitted to bake, cook, keep warm, kindle fire, prepare and do all that is necessary on the holiday for Shabbos, for ourselves, and for all Jews who live in this city.
Ideally, the food should be eaten on Shabbos, for a number of reasons. One such reason is that an item used for one Mitzvah should be used for another Mitzvah too.
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