The 17th of Tammuz is a fast day commemorating the fall of Jerusalem, prior to the destruction of the Holy Temple. This also marks the beginning of a 3-week national period of mourning, leading up to Tisha B'Av.
The 17th of Tammuz is the first of four fast days mentioned in the prophets. The purpose of a fast day is to awaken our sense of loss over the destroyed Temple - and the subsequent Jewish journey into exile.
Agonizing over these events is meant to help us conquer those spiritual deficiencies which brought about these tragic events. Through the process of "Teshuva" - self-introspection and a commitment to improve - we have the power to transform tragedy into joy. In fact, the Talmud says that after the future redemption of Israel and the rebuilding of the Temple, these fast days will be re-dedicated as days of rejoicing and festivity. For as the prophet Zechariah says: the 17th of Tammuz will become a day of "joy to the House of Judah, and gladness and cheerful feasts."
Why are we fasting?
Five great catastrophes occurred in Jewish history on the 17th of Tammuz:
Moses broke the tablets at Mount Sinai - in response to the sin of the Golden Calf.
The daily offerings in the First Temple were suspended during the siege of Jerusalem, after the Kohanim could no longer obtain animals.
Jerusalem's walls were breached, prior to the destruction of the Second Temple in 70 CE.
Prior to the Great Revolt, the Roman general Apostamos burned a Torah scroll - setting a precedent for the horrifying burning of Jewish books throughout the centuries.
An idolatrous image was placed in the Sanctuary of the Holy Temple - a brazen act of blasphemy and desecration.
Originally, the fast was observed on the Ninth of Tammuz since that was the day Jerusalem fell prior to the destruction of the First Temple in 586 BCE. However, after Jerusalem fell on the 17th of Tammuz - prior to the destruction of the Second Temple - the Sages decided upon a combined observance for both tragedies, the 17th of Tammuz.
The Jewish customs
No eating or drinking is permitted from the break of dawn, until dusk. Pregnant and nursing women - and others whose health would be adversely affected - are exempted from the fast.
Should the day coincide with Shabbat, the fast is delayed until Sunday.
Bathing, anointing, and wearing leather shoes are all permissible.
The "Aneinu" prayer is inserted into the Amidah of Shacharis and Mincha by the chazan. Individuals insert it in Mincha only. Slichos and "Avinu Malkeinu" are recited.
Exodus 32:11, in which the "13 Attributes of Mercy" are mentioned, is read at both the morning and afternoon services. Isaiah 55:6 - 56:8, which discusses the renewal of the Temple service, is read as the Haftorah at the Mincha service.
Reprinted with permission of Aish