The Gemara in Masechet Shabbat (117b) states: “Our Sages taught: How many meals must one eat on Shabbat? Three.” Our Sages expound this from verses as is discussed there.
How Much Bread to Eat?
Several Rishonim (Ba’al Halachot Gedolot, Responsa of Geonim, Rabbeinu Yehuda Al-Barceloni in his Sefer Ha’Itim, and others) write that the amount of bread one must eat during each of these meals is an egg’s volume of bread, i.e. one must eat at least fifty-four grams of bread during each of these meals. Maran Ha’Chida rules accordingly in his Birkei Yosef (Chapter 291, Subsection 2). It seems that Maran Ha’Shulchan Aruch rules accordingly as well in Chapter 291, Section 1, and this is indeed the correct opinion according to Halacha.
Nevertheless, some disagree and write that eating an olive’s volume of bread, i.e. twenty-seven grams, is sufficient during each of the Shabbat meals. Some indeed explain Maran Ha’Shulchan Aruch as agreeing with this view as well. Thus, several Poskim write that if one is ill and it is difficult for one to eat an egg’s volume of bread, eating only an olive’s volume of bread is sufficient. Even so, Maran Rabbeinu Ovadia Yosef zt”l writes that the correct amount of bread for the Shabbat meals is an egg’s volume, as we have established.
The Amount of Time One Must Eat It In
We have already established in the past that one may only recite Birkat Hamazon if one has eaten an olive’s volume of bread within the amount of time it takes to eat half a loaf of bread, i.e. approximately seven-and-a-half minutes. The same applies to the Shabbat meals in that one must make sure to eat an olive’s volume of bread (twenty-seven grams) within a timespan of seven-and-a-half minutes, for if not, one may not recite Birkat Hamazon and one has not fulfilled one’s obligation of eating the Shabbat meal. Thus, everyone should take care to be wise and eat an olive’s volume of bread within seven-and-a-half minutes at the beginning of the meal and only then to partake of other foods so as not to come to a point of overeating and not being able to recite Birkat Hamazon in accordance with Halacha. After eating the prescribed olive’s volume of bread, one may then eat whatever one wishes.
There is no distinction between men and women regarding this law, for women are equally obligated in all of the Mitzvot of Shabbat, just as men are.
