Ready And Able
‘Unripe Dates Are Unsuitable For An Eruv’
Food that comes in contact with tumah becomes ritually defiled as well. However, inedible fruit is not classified as food and, as such, is not susceptible to tumah. Inedible foods can’t be used for eruvin for the same reason: they’re not considered food.
R. Yehuda (28a) cites R. Shmuel b. Shilas who said in the name of Rav that kafniyos – unripe dates in their early stages – are unsuitable for an eruv. Presumably, this is so because these dates are not halachically considered food (since they are bitter and thus inedible). The Gemara (28b), however, also cites a baraisa that states that kafniyos are susceptible to tumah. The only way they can be susceptible to tumah is if they are halachically considered to be food. How then can Rav rule that they are not food?
The Gemara answers that the laws of eruvin and tumah have different criteria for determining what is considered food. For tumah, even bitter fruits such as kafniyos are classified as food since they can be made edible by cooking and sweetening. For eruvin, however, the food has to be edible as is (at the onset of Shabbos when the eruv takes effect).
The Gaon Yaakov (supra 27a s.v. “kal shekein”) cites the Ritva (supra 26b) who explains that an eruv must be fit to be eaten for one’s Shabbos meal, and since one may not cook on Shabbos the eruv may only consist of readily edible foods.
According to the Ritva’s reasoning, unripe dates (or raw vegetables which require cooking) should be suitable for an eruv techumim on yom tov since it is permitted to cook on yom tov.
The Gaon Yaakov, however, infers from Rashi (28b s.v. “v’yachol l’mesaken”) that he would not agree with the Ritva’s view, for he says that food used for an eruv has to be edible at that moment (needing no preparation whatsoever). Thus, even though one may cook on yom tov items like kafniyos are unacceptable for an eruv since they require preparation.