by Rabbi Yair Hoffman Sometimes, both the doctor and the Rav will tell a person not to fast on Yom Kippur.  Under such circumstances, one must reach out to one’s Posaik or Rav as to what to do. For those who cannot reach their Rav, however, what follows are the emergency amounts that one may eat or drink- if it is absolutely necessary.  It is called “Eating less than the shiur” and – when medically necessary – is what is done on Yom Kippur. CHATZI SHIUR – “THE BELOW THE THRESHOLD” PROHIBITION There are actually two different prohibitions that are violated when a regular person eats on Yom Kippur. The less commonly known prohibition is called “below the threshold prohibition” or the “Chatzi shiur prohibition.” Although this prohibition is a Torah one, it does not invoke the serious punishment of Karais. It is also set aside whenever there is anyone who is dangerously ill. But what about the regular “above-the-food-threshold” prohibition? May a dangerously ill person violate this regular prohibition if he can be eating “below the threshold?” Although this issue is actually a debate , the consensus of opinion is that if it is completely feasible from a medical perspective, such a person should just eat and drink “below the threshold.” PARAMETERS OF “BELOW THE THRESHOLD” What are the parameters of “below the threshold?” The parameters involve both time and food amounts. The “food amounts” are volume measures – not weight measures. And guess what? Food and drink are different – very different. FOOD AMOUNTS The food measurement is a constant –two thirds of a medium egg (see SA OC 618:7) – understood as one fluid ounce. The liquid measure varies according to each person. If it is determined that the patient should be fasting on Yom Kippur, then if feasible, the maximum quantity of food that may be eaten at one eating session is one fluid ounce – or 30 milliliters (ccs). It is a good idea to prepare these amounts in schnapps cups in advance. Proteins are, of course, more filling than starches. LIQUID AMOUNTS The amount for liquids varies – depending upon the person’s individual cheek volume . Remember, it is not a mouthful, but rather a cheekful – one side of the mouth. For the average person one can figure 35 milliliters. For a small person it could be 30 milliliters. All this refers to regular water. However, a few years before his passing (before Yom Kippur of 5769), Rav Elyashiv zatzal ruled that a person could actually use a different option – consuming water that has a Pagum (unnatural) taste that is not normally consumed because of its negative taste. The rationale for this ruling (based upon a Ramah) is that such drinking does not constitute a normal form of drinking and is thus only forbidden by Rabbinic ruling. The Rabbis, however, never made such enactments for people that are dangerously ill. More on this will follow in the next section. ANTIBIOTICS There are some people who have some life-threatening illnesses that require the consumption of a very potent anti-biotic. These anti-biotics must be consumed with a significant amount of water. Because of this, the Pagum water suggestion of Rav Elyashiv zt”l would be the most appropriate approach to this dilemma. But, what should […]