Shimon, the second son of Jacob and Leah and the progenitor of the Israelite tribe of Shimon, was born on Tevet 21 (according to another opinion, on Tevet 28), of the year 2194 from creation (1567 BCE), nine years after Jacob's arrival in Charan.
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On December 23 (21 Teves), 1690, strong earthquakes rattled the city of Ancona, Italy, causing numerous structures to collapse and placing its inhabitants in mortal danger. Miraculously, the Jewish quarter was spared, suffering the collapse of only one house. In commemoration of this event, the local Jewish community established that date as a day of celebration and song, while the previous day—20 Teves—would be marked yearly by fasting and charity (Or Boker, p. 48a).
When the spies that Moses sent returned from their reconnaissance of the Land of Canaan, they included in their report these words:
“We felt like ants before them,
and so we were in their eyes.”
Because they felt like ants in their own eyes,
therefore, others saw them as ants as well.