Daf Yomi - Sukkah 5 - No Dates Today

The Gemara states that the source for any of the quantities pertaining to the mitzvos is halacha le’Moshe mi’Sinai (a tradition received by Moshe at Sinai). Rashi cites two examples; in general, forbidden foods may not be consumed at a quantity equivalent to the size of an olive, and on Yom Kippur, any food equaling the size of a date or more may not be eaten.
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There is an interesting discussion regarding the definition of the prohibition to eat on Yom Kippur. Is the prohibition defined as eating per se, with the quantity being established as the equivalent of a date’s size since that eases the hunger, or is the prohibition to ease your hunger which is generally done by eating a date sized piece of food. This may sound like a play on words, but this question actually has some serious halachic implications. Consider the following- what happens if a person ate a little less than the equivalent of a date right before Yom Kippur and is still somewhat hungry. As Yom Kippur begins, he eats a little bit more, and it combines with what he ate before Yom Kippur to ease his hunger. This person has eased his hunger on Yom Kippur, but without eating the full forbidden quantity! The K’sav Sofer says that in such a case the person has indeed transgressed Yom Kippur. Obviously, he holds that the issue is eaing the hunger, and not the eating per se. Along similar lines, R’ Chaim Ozer Grodzinsky, in his sefer Achiezer, discusses intravenous feeding on Yom Kippur. If the prohibition is eating per se, it would be permitted. If, however, the prohibition is easing hunger, intravenous feeding may be prohibited as well.

According to the Ksav Sofer, the size of a date is not an amount which the Torah prohibits, satiation is prohibited. Rashi, who states that the size of a date on Yom Kippur is an amount which is learned from a halacha le’Moshe mi’Sinai seems to be saying not like the Ksav Sofer and rather that eating is prohibited and the amount is food in the size of a date.