346_001 - תענית אסתר - Ta'anis Esther: The Secret Behind the Name

From Rulings and insights from the Lubavitcher Rebbe - Rabbi Chaim Wolosow by R Chaim Wolosow.

The Rebbe explains that while the 13th of Adar was a day of war, the fast is named for Esther because she was the only one who could fast. Since the rest of the nation had to fight, Esther’s fast in the palace became the spiritual engine that fueled the Jewish people's physical victory. https://www.torahrecordings.com/shulchan_menachem/orach_chayim/346_001