Point Of Ingestion
“The Size of an Egg to Satisfy…”
The Mishnah (73b) states that one has to eat at least the volume of a large date (ke’koseves hagassah) on Yom Kippur in order to incur the penalty of kares. The Gemara (79b) concludes that a ke’koseves hagassah is larger than a kezayis (an olive’s volume) but smaller than a kebeitzah (an egg’s volume).
A kezayis is the minimum shiur for “achilah” (such as eating matzah on the Seder night) and a kebeitzah is the minimum shiur for “sevi’ah” (such as Birkas Hamazon, according to R. Yehuda). But eating on Yom Kippur has a different shiur because the Torah speaks in terms of affliction, and the Sages determined that food equaling the volume of a large date is sufficient to ease one’s innuy.
R. Yochanan (Chullin 103a) asserts that if one swallows half a kezayis of forbidden food, and then expels it, and then swallows it again, he receives malkos since a kezayis in total has passed through his throat (even though he only ingested half a kezayis). R. Yochanan maintains that the critical factor in determining whether one receives malkos is “hana’ah bi’gerono” – the pleasure of the throat. Reish Lakish disagrees and states that the stomach must derive pleasure. The halacha follows R. Yochanan.
Alleviating Hunger: The Fix
Rav Shamshon Raphael Hirsch (Responsa Shemesh Marpei, O.C. 19-22) was asked whether taking suppositories that quell hunger is permitted on Yom Kippur since the throat derives no pleasure from them. If yes, perhaps elderly people should be advised to take them.
In response, Rav Hirsch rules that taking suppositories to quell one’s hunger is forbidden (even though they do not provide pleasure to the throat) since the essential factor on Yom Kippur (unlike other issurim regarding food) is yisuvei da’atei (easing one’s discomfort). (Note: Of course, this ruling does not pertain to cases of pikuach nefesh when even eating is permitted.)
Satisfying Hunger: Satiation
The Chasam Sofer (Responsa Orach Chayyim 127) also distinguishes between eating on Yom Kippur and other issurim regarding food, writing that with regard to Yom Kippur the critical factor is “hana’as mei’av” – pleasure of the stomach rather than pleasure of the throat.
(In a similar vein, the Panim Meiros (Vol. II:27) submits with regard to Birkas Hamazon, that one is not required to recite Birkas Hamazon min haTorah unless the food is satisfying [“vesava’ta”]. If one eats half a kebeitzah, expels it, and then re-swallows it, he is not required to recite Birkas Hamazon.)
The Joys Of Eating
Rav Chaim Ozer Grodzinski (Responsa Achiezer vol. 3:61), however, disagrees and deduces that the issur of eating on Yom Kippur depends on hana’as gerono – the pleasure of the throat – just like other issurim regarding food. As proof, he cites the Gemara (Shevuos 13b) which offers the case of a person choking while eating on Yom Kippur as an example of someone who dies without attaining the atonement of Yom Kippur. Even though the person choked and died before the food entered his stomach, he sinned. This proves, says Rav Chaim Ozer Grodzinski, that the essential factor regarding Yom Kippur is the pleasure of the throat, not the pleasure of the stomach. Consequently, he permits a sick person to take food or liquid through a feeding tube (or intravenously) on Yom Kippur since it lacks the critical factor of “pleasure of the throat.”