Tomorrow marks a fast day on the Jewish calendar — The 10th of Tevet, which is one of four Jewish fast days that commemorate difficult times in Jewish history.

The others are Tisha B'Av (the day of the destruction of both Holy Temples in Jerusalem), the 17th of Tammuz (the day the defensive wall of Jerusalem was breached by Titus and the Roman legions in A.D. 70) and the third of Tishrei (the day that marks the assassination of the Babylonian-appointed Jewish governor of Judah, Gedaliah ben Achikam).

The 10th of Tevet marks the genesis of the siege of Jerusalem by Nebuchadnezzar, the king of Babylonia, and the beginning of the battle that ultimately destroyed Jerusalem and the Temple of Solomon, and sent the Jews into the 70-year Babylonian Exile.

In the modern era, the 10th of Tevet has become the day to mark mass murder of Jews throughout history, culminating in the wholesale massacres of Jews, which took place during the dark years of 1939-1945.

This year, the fast on the 10th of Tevet assumes special significance, with one million people in Israel instructed by the Israel Home Front Command to stay near their shelters while Israel's adveraries use their air waves to convey one message: Destroy the Jews.