Tishah B’Av after Chatzos
The halachos of mourning that apply on Tishah B’Av apply after chatzos (midday) as well. There are some restrictions, though, that are somewhat relaxed after chatzos, and among them, according to some opinions, regular shiurim that people have after davening. The specific example cited in poskim is the Tehillim people recite every day after davening. Learning Torah, however—except for material associated with mourning or the destruction of the Beis Hamikdash, such as the book of Iyov, parts of the book of Yirmeyahu, Midrash Eichah, and similar texts—is forbidden in the afternoon as well.
One is not required to sit on the ground or lower than usual after chatzos, although poskim question the reason for that, as the concept of mourning applies to the afternoon as well. The Chida brings a very interesting minhag (Jewish custom) that although it is forbidden to do work on Tishah B’Av, there were many women who scrubbed and washed their floors on Tishah B’Av afternoon in anticipation of Moshiach’s arrival; the rabbonim permitted them to continue
this minhag in order to bolster their faith in the Geulah (Redemption). The Arizal mentions that Moshiach, whose name is Menachem (consolation), was born on Tishah B’Av afternoon, which is why we say the tefillah of Nachem at that time. May it be Hashem’s Will that Tishah B’Av be transformed into a Yom Tov very, very soon. #364