The three-week period between Shiva Asar Be’Tamuz and Tisha B’Ab is known as "Ben Ha’mesarim," during which we observe certain practices to mourn the destruction of the Bet Ha’mikdash.
The Arizal (Rabbi Yishak Luria, 1534-1572) wrote that it is proper during this period for "Hasidim Ve’anshe Ma’ase" (particularly pious and devoted people) to recite each day the "Tikun Rahel" section of the "Tikun Hasot" prayer, which us printed in many Siddurim. The "Tikun Rahel" contains many verses describing the destruction of the Bet Ha’mikdash, and its recitation thus helps put a person in the proper frame of mind for this period of mourning. Many recite this service each night throughout the year as part of the "Tikun Hasot" prayer, but the Arizal held that it is proper to recite it as well every afternoon during the three weeks between Shiva Asar Be’Tamuz and Tisha B’Ab. The recitation should take place from Hasot (midday as defined by Halacha) until the point of "Minha Ketana" in the late-afternoon hours. This practice is also mentioned by the Hida (Rabbi Haim Yosef David Azulai, 1724-1806), in his works Yosef Ometz and More Be’esba.
Hacham Ben Sion Abba Shaul (Israel, 1924-1998) ruled that one should not recite "Tikun Rahel" on days marking joyous occasions, such as on Friday afternoon, when we prepare to welcome the Shabbat, as well as Shabbat itself. It should likewise be omitted on Rosh Hodesh Ab and on Ereb Rosh Hodesh Ab. On days when a person omits Tahanun due to a personal celebration, such as a Mohel (person performing a circumcision), a Sandak (one who holds the child during circumcision) and the father of a child on the day of a circumcision, one should omit "Tikun Rahel," as well. The festive nature of these occasions requires omitting the somber recitation of "Tikun Rahel," which, as mentioned, speaks of the tragedy of the Temple’s destruction.
Furthermore, one should not recite "Tikun Rahel" during the afternoon of Tisha B’Ab, when we begin turning our attention away from mourning and toward our hopes and anticipation of redemption. Since at this time we focus on the prospect of redemption rather than on the tragedy of the destruction, it is inappropriate to recite "Tikun Rahel."
The authorities debate the question of whether this custom applies in Israel during a Shemita ("sabbatical") year. Those who normally recite "Tikun Hasot" every night omit "Tikun Rahel" in Israel throughout the entire Shemita year, as the status of Shemita resembles that of Shabbat and festivals. The question thus arises as to whether the afternoon recitation of "Tikun Rahel" during the three weeks should be observed in Israel during the Shemita year. Rabbi Eliyahu Mani (Baghdad-Israel, 1824-1899) held that the recitation during the three weeks is no different in this regard from the nighttime recitation throughout the year, and it thus should be omitted in Israel during the Shemita year. Rabbi Yaakov Haim Sofer (Baghdad-Israel, 1870-1939), however, in his Kaf Ha’haim (551:224), disagreed, and maintained that one should recite "Tikun Rahel" during the three weeks of a Shemita year in Israel. This was the view accepted by Hacham Ben Sion Abba Shaul. (It should be emphasized that this debate relates only to the recitation of "Tikun Rahel" in Israel; outside Israel, all authorities agree that "Tikun Rahel" is recited as usual during the Shemita year.)
One should not mistakenly think that this practice is reserved for Kabbalists or great scholars. Reciting "Tikun Rahel" during the three weeks is a most beneficial practice for all people, as it sets the mood and puts one in the proper mindset for the period of mourning. Reading these verses can be very inspiring and bring a person to a greater appreciation of the tragedy of the Temple’s destruction, and to a more profound sense of loss. It should be noted that during the three weeks in Yeshivat Porat Yosef, after the first learning session in the early afternoon all the students sit on the floor and recite "Tikun Rahel." This is thus a practice that all people should observe, in order to enhance one’s awareness of the immense tragedy of the Hurban (destruction).
Summary: It is proper to recite the "Tikun Rahel" section of "Tikun Hasot" service every afternoon during the three weeks between Shiva Asar Be’Tamuz and Tisha B’Ab, except on festive occasions such as Ereb Shabbat, Shabbat, Rosh Hodesh Ab and Ereb Rosh Hodesh Ab. It is not recited on the afternoon of Tisha B’Ab. According to some authorities, "Tikun Rahel" is not recited in Israel during the Shemita year.
