2. The Fast of Gedaliah is one of the four fasts related to the destruction of the First Temple.
3. It was ordained to remember the assassination of Gedaliah, who was appointed the commissioner of Judea shortly after the destruction of the First Temple. His murder was the final nail in the coffin of the First Temple.
4. After the conquest of the kingdom of Judah by the Babylonians, most of the Jewish people went into exile to Babylon, including all the dignitaries of the nation, while only a few poor people remained in the country who worked as vintners and farmers.
Nebuchadnezzar II, the king of Babylon, appointed Gedaliah the ruler of the survivors who remained in Judea. Gedaliah gathered together and led all these survivors of the destruction. He convinced them to harvest their crops and go ahead with their lives. He received backing from the prophet Jeremiah who joined him at his seat of government.
5. As described in the book of Jeremiah, Gedaliah was murdered by a group of Jews led by Ishmael ben Netanya, who was a scion of the royal family. Ishmael ben Netanya was jealous of his position of power. Gedaliah was warned by his followers, including his military commander Jochanan ben Korach and his men, of what Ishmael was planning. Jochanan even asked Gedaliah to preempt Ishmael and kill him first, but Gedaliah did not believe him and refused the offer. Gedaliah was murdered as he sat in his outpost (probably today's Nebi Samuel), and his supporters and the Babylonian soldiers stationed there were also massacred. The massacre was done under the direction of Ellis, the king of Ammon, in the midst of a banquet which Gedaliah had made for Ishmael ben Netanya and his men.
6. Gedaliah’s murder ended the existence of the Jewish autonomy in the Land of Israel after the destruction of the First Temple. The murder caused the poor people who lived under Gedaliah’s government to disperse. Fearing the reaction of the Babylonians, some of them went to Egypt. This sealed the destruction of the First Temple, and there was no Jewish sovereignty in Israel for the following seventy years until the return to Zion in the days of Ezra.
7. There is a dispute over whether Gedaliah was murdered on the third day of Tishrei, or was murdered of the first of Tishrei and the fast was postponed until after Rosh Hashana because fasting is not permitted on a holiday.
8. The fast begins at dawn and ends when the stars come out.
9. For the duration of the fast, nothing may be eaten or drunk.
10. A special supplication (Selichot) is recited for the Fast of Gedaliah in the morning prayers. We also add “Aneinu” in the Shemoneh Esreh prayer (Sephardim recite it in the morning and afternoon prayers, and Ashkenazim recite it only in their afternoon prayers). For the Torah reading, we read the passage of “Vayechal Moses” which is read on fast days.