Tisha B'av started out as a day of lamentation over the destruction of the first Holy Temple. According to the Book of Kings 2, the destruction of the first Holy Temple occurred on the seventh day of the fifth month and according the prophet Jeremiah, who lived and was active in Jerusalem and in the Holy Temple, the destruction occurred on the tenth of this month. The prophet Zechariah, who was active in the era of the return of the exiled Jews to Israel, prophesized that this fast day, as well as the other fast days marking the process of the destruction, would be ultimately reformed to a day of festivity and joy.
The date – the ninth of Av, is first mentioned in the Mishnah in the tractate of Ta'anit, and is marked as the date of occurrences of five sad events the nation had historically experienced:
'on this day it was decreed that our ancestors would not enter the Land of Israel': this entailed the decree of the wandering of the Children of Israel in the wilderness following the sin of the spies after the exodus from Egypt.
'and the temple was initially destroyed': the destruction of the first temple.
'and the second time': the destruction of the second temple.
'and Beitar was captured': the city of Beitar, the stronghold of the rebels during the revolt of Bar Kokhba was seized.
'and the city was plowed': the plowing of the area of the temple ruins and the City of Jerusalem following the Bar Kokhba revolt.
Throughout the generations, the Jewish tradition added a long row of calamities that had occurred around the date of Tisha B'av.
> The Story
Tisha B'av marks the peak of the days of mourning that commence on the 17th of Tamuz, and it is the most severe fast day of all the four fast days established to commemorate the destruction of the Holy Temple. In contrast to the other fast days, which are shorter, the fast of Tisha B'av lasts for the entire day, from evening to evening, and throughout the day, it is traditionally prohibited to eat, drink, lubricate, bathe, to wear leather footwear and to engage in intercourse. In addition to these prohibitions it is customary to sit on low seats and to refrain from Torah study. It is customary to open the fast by the reading the Book of Lamentations, and by reciting elegies over the calamities mentioned throughout the day.
> In Zionism
With the rebuilding of the settlement in Israel in the Zionist era, this date had lost its status among the secular public. And its status became questionable. Berl Katznelson's sharp criticism over the counsellors of The Immigrant Camps Movement for setting this date as the date slated for setting out to summer camps is well known. Berl complained about the alienation of the youth counsellors from the tradition of Jewish history, and maintained that as long as the exile still exists and parts of the Jewish nation are still undergoing affliction, Tisha B'av ought not to be forgotten. Despite this criticism, and since this date is marked as such for the summer vacation by the National Educational System, Tisha B'av had no significance for the secular Israeli society and it remained a date marked primarily by the religious public. With the consolidation of the State of Israel, the importance and character of this date ought to be reconsidered, with a status that would mark it somewhere between a day of mourning over the destruction to a day of joy over the construction of the state.