|Seventeenth of Tammuz|
|Official name||Hebrew: שבעה עשר בתמוז|
|Type||Jewish religious and national|
|Significance||Date when the walls of Jerusalem were breached|
|Date||17th day of Tammuz|
|2018 date||July 1, dawn to nightfall|
|2019 date||July 21, dawn to nightfall|
|Related to||The fasts of the Tenth of Tevet and Tisha B'Av, the Three Weeks & the Nine Days|
The Seventeenth of Tammuz (Hebrew: שבעה עשר בתמוז Shiv'ah Asar b'Tammuz) is a Jewish fast day commemorating the breach of the walls of Jerusalem before the destruction of the Second Temple. It falls on the 17th day of the 4th Hebrew month of Tammuz and marks the beginning of the three-week mourning period leading up to Tisha B'Av.
The fast of Tammuz, according to Rabbi Akiva's interpretation, is the fast mentioned in the Book of Zechariah as "the fast of the fourth [month]" (Zechariah 8:19). This refers to Tammuz, which is the fourth month of the Hebrew calendar.
The Book of Jeremiah (39.2, 52.6–7) states that the walls of Jerusalem during the First Temple were breached on the 9th of Tammuz. Accordingly, the Babylonian Talmud dates the third tragedy (breach of Jerusalem's walls) to the Second Temple period. However, the Jerusalem Talmud (Taanit IV, 5) states that in both eras the walls were breached on 17th Tammuz, and that the text in Jeremiah 39 is explained by stating that the Biblical record was "distorted", apparently due to the troubled times.
The Seventeenth of Tammuz occurs forty days after the Jewish holiday of Shavuot. Moses ascended Mount Sinai on Shavuot and remained there for forty days. The Children of Israel made the Golden Calf on the afternoon of the sixteenth of Tammuz when it seemed that Moses was not coming down when promised. Moses descended the next day (forty days by his count), saw that the Israelites were violating many of the laws he had received from God, and smashed the tablets.
Not only did the sieges of Jerusalem during the First and Second Temple periods occur on, or near, this date, but the breach of the walls of Jerusalem during the First Crusade occurred on the 17th of Tammuz.
As a minor fast day, fasting lasts from dawn to shortly after dusk. It is customary among Ashkenazi Jews to refrain from listening to music, public entertainment, and haircuts on fast days, and on this occasion because it is also part of The Three Weeks (see below, Bein haMetzarim); other deprivations applicable to the major fasts (i.e. Yom Kippur and Tisha B'Av) do not apply.
If the 17th of Tammuz falls on a Shabbat, the fast is instead observed the next day, the 18th of Tammuz. This last happened in 2018, and will happen again in 2019.
A Torah reading, a special prayer in the Amidah (Aneinu), and (in many congregations) Avinu Malkenu are added at the morning Shacharit and afternoon Mincha services. Ashkenazi congregations also read a haftarah (from the Book of Isaiah) at Mincha. Congregations also recite during Shacharit a series of Selichot (special penitential prayers) reflecting the themes of the day.
The 17th of Tammuz is the second of the four fasts commemorating the destruction of the Temple and the Jewish exile. It is preceded by the fast of the Tenth of Tevet and arrives three weeks prior to the full-day fast of the Ninth of Av. The cycle is also associated historically with the Fast of Gedalia, which is observed on the third day of Tishrei.
The three weeks beginning with the 17th of Tammuz and ending with the Ninth of Av are known as Bein haMetzarim ("between the straits", i.e. between the days of distress), or The Three Weeks. Some customs of mourning, which commemorate the destruction of Jerusalem, are observed from the start of the Three Weeks.
The oldest extant reference to these days as Bein haMetzarim – which is also the first source for a special status of The Three Weeks – is found in Eikhah Rabbati 1.29 (Lamentations Rabbah, fourth century CE?). This midrash glosses Lamentations 1:3, "All [Zion's] pursuers overtook her between the straits."
The three weeks of mourning between the 17th of Tammuz and 9th of Av is cited as a rabbinically instituted period of fasting for the "especially pious". Such fasting is observed from morning to evening, common with other rabbi-decreed fasts.
The fast of the 17th of Tammuz coincides with American Independence Day every 10 to 20 years (most recently in 1996 and 2015, and will happen again in 2034 and 2080). The most famous of these occurrences was on July 4, 1776, when the United States declared independence.