Chapter 124:15-17
Laws Of Tish'ah B'av
15. Regarding working [on Tish'ah B'av], it is our custom to forbid all
"melacha" ("creative physical activity") that takes time, even if it is
merely a simple task that does not require professional expertise (1);
[this prohibition applies] during the night and during the day until midday
("chatzos") (2). A task that does not take time, for example, lighting
candles or tying a knot, is permitted (3). After midday, all "melacha" is
permitted (4) .
Similarly, it is customary to forbid business transactions ("masah
u'matan") before midday; after midday, it is permissible.
Nevertheless, a G-d fearing person should be stringent and not engage in
"melacha" or commercial activity throughout the entire day, so that his
attention will not be diverted from mourning.
[Before midday] all activities may, however, be performed by a Gentile (5),
and one may also personally perform an activity that is necessary to
prevent a financial loss ("davar ha'avud") (6). It is preferable to have
cows milked by a Gentile. When that is impossible, one may milk them oneself.
16. It is customary not to sit on a chair at night, nor during the day
until after midday. Rather, one should sit on the ground (7). After
midday, one may sit on a chair. [This is the only form of deprivation which
is ceased in the middle of the day, whereas,] the other prohibitions (such
as not washing or wearing leather shoes) continue until the appearance of
stars.
17. It is customary not to begin preparing for the [evening] meal until
after midday. For an event associated with a mitzvah, one may [begin
preparations earlier].
FOOTNOTES:
(1) The reason for the prohibition is so that people's minds will not be
diverted from mourning.
(2) Halachic midday, "chatzos," is calculated by totaling the number of
minutes from dawn ("alos ha'shachar") until the appearance of 3 stars
("tzeis ha'kochavim"), and then dividing it in half (some say from sunrise
to sunset).
(3) There is a dispute among the authorities regarding the act of writing;
some rule that it is permitted, while others rule that the same laws apply
here as on Chol HaMoed, and it is prohibited under most circumstances (See
Beur Halacha 554:22).
(4) Even housework (making beds, sweeping) should be postponed until after
midday. Some authorities rule that, wherever possible, it should be avoided
the entire day (Aruch HaShulchan 559:9). Even when work is permissible, one
should minimize one's involvement as much as possible, so as not to
distract one's mind from mourning.
(5) It is permissible as long as the work performed by the Gentile is not
publicly visible, for example, construction or painting the outside of a
house (Mishna Berura 554:46).
(6) Where possible, it should be performed by a Gentile, or, at least
postponed until after midday. Preventing a financial loss includes buying
something on sale that will not be available at that price after Tish'ah B'av.
(7) The Mishnah Berurah (559:11) permits sitting on a pillow or on a low stool.
