Tzom Gedaliah (Fast of Gedaliah) is an annual fast day instituted by the Jewish Sages to commemorate the assassination of Gedaliah Ben Achikam, the Governor of Israel during the days of Nebuchadnetzar King of Babylonia. As a result of Gedaliah's death the final vestiges of Judean autonomy after the Babylonian conquest were destroyed, many thousands of Jews were slain, and the remaining Jews were driven into final exile.
The fast is observed on the day immediately following Rosh Hashanah, the third of Tishrei. In the Prophetic Writings this fast is called 'The Fast of the Seventh' in allusion to Tishrei, the seventh month.
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