The Fast of Shiva Asar B'Tammuz is held on the 17th day of Tammuz, which is the fourth month of the Hebrew calendar.
It observes five calamities that affected the Jewish people. These are: (1) Moses broke the tablets of stone and (2) an idol of “Zeus” was erected in the temple (3) the daily sacrificial offerings were discontinued in 423 BCE; (4) Jerusalem’s walls were breached in 69 BCE; and (5) the Roman military leader Apostomus burned a Torah scroll possibly around 50 CE just before the Bar Kokhba revolt.
What do people do?
Many Jewish people fast from dawn until nightfall by abstaining from food and drinks. However, people who are ill or weak, children and pregnant or nursing mothers may not fast completely but only eat simple food. In addition, special prayers are recited and sections of the Torah and Haftarah (Haftorah, Haptara) are read during the morning and evening services. In contrast to some fast days, Jewish people may be permitted to wear leather and wash themselves on the 17th of Tammuz.
Public life
The Fast of Shiva Asar B'Tammuz, also known as the 17th (or Seventeenth) of Tammuz, is not a public holiday in Israel.
Background
The 17th day of Tammuz is a day of mourning for Jewish people. It marks the anniversary of five calamities. On this day in the year 1313 BCE, Moses broke the tablets of stone that were inscribed with the Ten Commandments and the idol of “Zeus/Jupiter” was erected in Jerusalem’s temple.
On this date in the year 423 BCE, the daily sacrificial offerings were discontinued in the run up to the destruction of the first temple. In the year 69 BCE Jerusalem’s walls were breached, which resulted in the destruction of the second temple. Finally, the Roman military leader Apostomus burned a Torah scroll, possibly around 50 CE. This may have contributed to the Bar Kokhba revolt, the last war between the Romans and the Jews between 132 and 135 CE.
The 17th of Tammuz marks the start of the “Three Weeks” (Bein HaMetzarim) leading up to Tisha B'Av. Which is a period of mourning marking the destruction of both the First Temple and the Second Temple in Jerusalem. During the “Three Weeks”, it is customary to spend extra time studying Jewish law, to give extra charity and not to hold joyous celebrations, such as weddings, or wear new clothes.
Source/See: Fast of Shiva Asar B'Tammuz Observances
