The "Three Weeks" between the 17th of Tammuz (July 5) and the Tisha B’Av (July 26) have historically been days of misfortune for the Jewish people. During this time, both the First and Second Temples were destroyed, among other terrible tragedies.
On Shabbat during the Three Weeks, the Haftorahs are taken from chapters in Isaiah and Jeremiah dealing with the Temple's destruction and the exile of the Jewish people.
During this time, some aspects of mourning are observed. We minimize celebrations. In addition, we avoid potentially dangerous or risky endeavours.
ASPECTS OF MOURNING DURING THE THREE WEEKS
(1) No weddings are held. (However, engagement ceremonies are permitted.)
(2) We do not listen to music. Live or recorded.
(3) We avoid all public celebrations- especially those which involve musical accompaniment.
(4) No haircuts or shaving.
(5) We do not say the blessing She-hechianu on new food or clothes, except on Shabbat.
THE NINE DAYS
The period commencing with Rosh Chodesh Av is called the "Nine Days." During this time, a stricter level of mourning is observed, in accordance with the Talmudic statement (Ta'anit 26): "When the month of Av begins, we reduce our joy.”
(1) We avoid purchasing any items that bring joy.
(2) We suspend home improvements, or planting of trees and flowers.
(3) We avoid litigation with non-Jews, since this is not a positive time of year for the Jews.
(4) We abstain from the consumption of meat (including poultry) and wine. These foods are symbolic of the Temple service, and are generally expressions of joy.
• On Shabbat, meat and wine are permitted. This applies also to any other seuduat mitzvah -- for example, at a Brit Milah or at the completion of a tractate of Talmud.
(5) We refrain from wearing newly laundered garments, or laundering any clothes.
• Fresh clothes may be worn for Shabbat.
• The clothing of small children, which gets dirty frequently, may be washed during the Nine Days.
• Clothes may not be laundered even if done in preparation for after Tisha B'Av, or even if done by a nonJew.
(6) We do not bathe for pleasure