The Torah commands in Parashat Emor (Vayikra 23:27) that on the 10 th day of the month of Tishri – the day of Yom Kippur – we are required to “afflict our souls” (“Ve’initem Et Nafshotechem”). The Sages understood this as a reference to “Dabar She’me’abed Et Ha’nefesh” – something which “reduces” the body, meaning, fasting, abstaining from food and drink. In addition, we are to refrain on Yom Kippur from four other types of physical enjoyment – bathing, applying oil or ointment to the skin, wearing shoes, and marital relations. The Rishonim debate the question of whether these four activities are included in the Torah command to “afflict our souls” on Yom Kippur, or are forbidden Mi’de’rabbanan (by force of Rabbinic enactment). According to some opinions, Torah law forbids only eating and drinking, and the Sages later enacted that we abstain also from these other four forms of physical enjoyment. The Sefer Ha’hinuch explains that in G-d’s infinite kindness, He designated a day on which we attain forgiveness for our wrongdoing through repentance. We are to refrain from food and drink on this day, the Sefer Ha’hinuch writes, because physical activities have the effect of drawing us toward our physical desires, away from the pursuit of wisdom and the service of G-d. The Sefer Ha’hinuch explains that the true “sweetness” of life is Torah study and Misva observance, whereas the physical pleasures of life are “artificial” sweetness. The more we involve ourselves in physical pleasures, the less likely we are to enjoy and pursue real joy, the joy of serving Hashem. Therefore, on Yom Kippur, when we are judged, we abstain from physical enjoyment to show that we are making an effort to draw ourselves toward the service of G-d. Normally, when the Torah forbids eating something, one transgresses the prohibition by eating a Ke’zayit. On Yom Kippur, however, since the Torah does not directly forbid eating, but rather requires “afflicting our souls,” the command is violated through the consumption of a “Kotebet Ha’gasa” – the volume of a large date, which is larger than a Ke’zayit. The Sages determined that it is only after eating this amount that one experiences a degree of satiation such that he no longer feels “afflicted.” One who drinks on Yom Kippur transgresses this command if he drinks the amount of “Melo Lugmav” (a cheek-full). Addressing the other four prohibitions, the Sefer Ha’hinuch opines that these are forbidden only “Mi’de’rabbanan,” and therefore, if a person has some particular need to perform one of these activities on Yom Kippur, he is allowed to do so. For example, a person with scabs in his scalp which cause him discomfort may apply ointment to alleviate the discomfort. One who needs to cross through water to guard his property, or for some other purpose, he may, even though he will then be bathing. Only leather shoes are forbidden to be worn on Yom Kippur; shoes made from other materials may be worn. An ill patient, Heaven forbid, for whom fasting can be life-threatening, may and in fact must eat on Yom Kippur in order to avoid danger. He may eat if an expert physician says that he must, and even if the doctor determines that his life is not threatened by fasting, he may eat if he feels that he must in order to protect his life. The Sefer Ha’hinuch mentions in this context that the fast of Tisha B’Ab, which the Sages enacted for the purpose of mourning the destruction of the Bet Ha’mikdash and other tragedies, features the stringencies of Yom Kippur. Meaning, the fast begins before sundown the day before, and all five prohibitions must be observed. Moreover, even pregnant women and nursing mothers are required to fast unless this poses a risk, just as they are on Yom Kippur. This command applies in all places and all times, to both men and women. One who eats or drinks the aforementioned quantities on Yom Kippur has transgressed this affirmative command, as well as a separate prohibition, which is punishable by Karet. O