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There is a mitzva to enjoy Shabbat by eating three meals. The first meal is on Friday night and the other two are on Shabbat day. The second meal should begin before midday, and the third meal should begin at least half-an-hour after midday (but no later than sunset).
These meals should include bread (the most important food) as well as other worthy food that people relish, such as meat, wine, and delicious fruit. Those who do not enjoy meat and wine should have foods they do appreciate. At the third meal (se’uda shlishit or shaleshudis), one who does not feel like eating bread may eat other food instead, since this meal is for extra gratification. However, the first two meals are so important that bread is required.
There is a mitzva to begin each Shabbat meal by reciting the blessing of Ha-motzi over two loaves of bread (leĥem mishneh), whether they are challahs, rolls, or other types of bread. This expresses the idea that Shabbat is doubly blessed, as represented by the double portion of manna the Israelites received on Fridays in the desert. The person making Ha-motzi should hold both of the challahs while reciting the blessing, but only needs to cut one of them.
Even though it is generally a positive character trait to eat sparingly, this is not the case on Shabbat, when eating is a mitzva. However, one should not go to the other extreme. Overeating makes a person feel sluggish and depressed, while Shabbat meals are meant to make subsequent Torah study more joyful and lively. Nevertheless, someone who is sleepy after lunch, should take a short nap and wake up with renewed energy for Torah study. Someone who is ill and has no appetite need not eat very much, since it is not pleasurable.
The Sages inserted a special passage honoring Shabbat in the Grace After Meals (Birkat Ha-mazon). Known as Retzei, it begins with the words “Retzei Ve-haĥalitzenu” (“Favor and strengthen us”).
