Between the 17th of Tammuz and Tisha B'av
8a.It is a universally accepted Jewish custom not to eat meat or drink
wine from Rosh Chodesh Av until Tish'ah B'av (1). It is forbidden to eat
even a dish that was cooked with meat or that contains animal fat
(2). Poultry is also forbidden. Nevertheless, a person who suffers harm
from eating dairy foods may eat poultry.
For a sick person, there are no restrictions (3). Nevertheless, if it is
not difficult for him, he should refrain [from eating meat] from the
seventh of Av onward. Similarly, some women after childbirth follow the
custom of not eating meat from the seventh of Av onward, because on that
day the Gentiles entered the Temple (See Chapter 124, Law 20) (4).
(1) Eating meat and drinking wine is a source of joy. In addition, this
custom reminds us of the animal sacrifices and wine libations that ceased
to occur once the Beis Hamikdash (Temple) was destroyed (Aruch HaShulchan
551:23). Not eating meat or drinking wine on Erev Tish'ah B'av during the
meal before the fast ("seuda hamafsekes") is a halacha, not simply a
custom. The Aruch Hashulchan (Ibid.) writes that when the Jewish people
accept a custom upon themselves, it is considered a communal vow ("neder
shel klall Yisroel"), and therefore, one who doesn't abide by that custom
is violating the biblical prohibition against breaking a vow.
(2) If the non-meat part was sixty times the volume of the meat, or if
there is no taste of meat in the food, it is permissible (Mishna Berura
551:63 and Sha'ar HaTziyun 69). Non-meat ingredients cooked in a meat
vessel are permissible (Ibid).
(3) However, it is best that he eat chicken if it would suffice for his
condition. Similarly, pregnant and nursing women may eat meat if they
experience difficulty eating dairy, however, chicken is preferable.
(4) Pregnant and nursing women should follow this custom if possible.