The Jewish Calendar and Holidays (incl. Sabbath): Other Holidays and Fasts: Purim not Being Mentioned in the Torah:
Why do we celebrate Purim when it isn't mentioned in the Torah?
Moses was commanded about many holidays, but not about the ones that celebrate events that occurred
after his time, such as Chanukah and Purim. Both of these holidays are Rabbinical institutions. The
acceptance of Purim as a holiday by the Jewish people is recorded in the Bible in Ch. 9 of the Book of Esther.
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