Moses Breaks Tablets (1313 BCE)
The Talmud (Taanit 28b) lists five tragic events in Jewish history that occurred on Tammuz 17, on account of which a fast was instituted on this day
The first of these occurred in 1313 BCE, forty days after the Giving of the Torah on Sivan 6.
1) Upon descending Mount Sinai and witnessing Israel's worship of the Golden Calf, Moses smashed the Tablets inscribed with the Ten Commandments which he was carrying down from the mountain.
2) The daily sacrificial offerings (Korban Tamid) in the Holy Temple were discontinued, three weeks before the Babylonians' destruction of the First Temple in 423 BCE.
The other three national tragedies mourned on Tammuz 17 are connected with the Roman conquest of Jerusalem and their destruction of the Second Temple in the year 69 Common Era:
3) The walls of the besieged city of Jerusalem were breached.
4) The Roman general Apostomus burned the Torah and,
5) placed an idol in the Holy Temple.
The fighting in Jerusalem continued for three weeks until the 9th of Av, when the Holy Temple was set aflame.
Links:The Destruction of the Holy TempleThe Three Weeks
Laws and Customs
Tammuz 17 is a fast day, devoted to mourning the breaching of Jerusalem's walls and the other tragic events that occurred on this day (see "Today in Jewish History") and repenting and rectifying their causes. We refrain from all food and drink from "daybreak" (about an hour before sunrise, depending on location) until nightfall. Special prayers and Torah readings are added to the day's services.
For eight hundred and thirty years there stood an edifice upon a Jerusalem hilltop which served as the point of contact between heaven and earth. So central was this edifice to the relationship between man andG-d that nearly two-thirds of the mitzvot are contingent upon its existence. Its destruction is regarded as the greatest tragedy of our history, and its rebuilding will mark the ultimate redemption-the restoration of harmony within G-d's creation and between G-d and His creation.A full three weeks of our year-the three weeks "between the strictures" of Tammuz 17 (July 9) and Av 9 (July 29-30)- are designated as a time of mourning over the destruction of the Holy Temple and the resultant galut-physical exile and spiritual displacement-in which we still find ourselves. -continue