Chapter 124:5
Laws Of Tish'ah B'av
5. The words of Torah bring joy to the heart, as [Psalms 19:9] states:
"The precepts of G-d are just, gladdening the heart." Therefore, it is
forbidden to study Torah on Tish'ah b'av, with the exception of those
subjects which evoke sadness; for example, [one may study] the prophecies
of retribution in the "Book of Jeremiah", but one should skip over the
comforting verses that are interspersed there. Similarly, it is permissible
to study the "Book of Job," and the midrash on the "Book of Eichah"
("Lamentations").
From the Talmud, one may study the laws of mourning and of ostracism that
are mentioned in the chapter "Eilu Megalchim" (the third chapter of "Mo'ed
Koton"), and the [description of the fall of Jerusalem and of Beitar] in
the aggados of the chapter "Hanizokin" (the fith chapter of
"Gittin"). From the Jerusalem Talmud, it is permitted to study the
conclusion of the tractate of "Ta'anis", which describes [the Temple's]
destruction (1).
Even those works that one is allowed to study, one may not study intensely,
investigating a question or an answer, or deriving a new concept, for this
brings a person happiness.
A person may also teach children those subjects he is allowed to study
himself. It is permitted to recite all those words of Torah that are
included in the daily order of prayer, even the chapter "Ezehu Mekomon"
(2). The order of "Ma'amodos", however, may not be recited, even though a
person is accustomed to reciting it every day.
FOOTNOTES:
(1) One may also study the story of the destruction in Sanhedrin (pg 104),
and in Josephus (Mishna Berura 554:3), as well as the laws of mourning in
the Shulchan Aruch and its commentaries.
(2) Parshas HaTomid, Ezehu Mekomon, and Rabi Yishmoel are all recited, but
not the rest of Korbanos (Ibid. 554:7).