Unique to the Jewish calendar, Purim is actually observed on different days depending on location.
The majority of the Jewish people celebrate Purim on the 14th of Adar (yesterday). However, Jews living in the city of Shushan (now the city of Shush, Iran), Jerusalem and all the cities that had walls at the time of Joshua’s conquest of Canaan, celebrate Purim on the 15th of Adar (today).
The delay in the Purim celebration is based on Esther 9:16-17.
“And the rest of the Jews in the states [not Shushan] of the king grouped together, protecting their lives, and were relieved of their enemies…on the 13th of the month of Adar, and they rested on the 14th, making it a day of feasting and joy. But the Jews in Shushan grouped together on the 13th and 14th, and rested on the 15th, making it a day of feasting and joy.”
The majority of the Jews were able to stop defending themselves on the 13th, and so rested on the 14th. In the capital city, however, where Haman’s evil plot had aroused greater hatred, the Jews were forced to defend themselves through the 14th as well, and rested on the 15th.
Mordechai and the great sages of the time felt that it was important to separate Shushan’s celebration from that of the rest of the people. Because they were still in exile, however, the sages wanted to make certain that the people remembered the holy city of Jerusalem and the Land of Israel. It was therefore declared that, in addition to Shushan, any city that was surrounded by a wall at the time of Joshua’s conquest of Canaan would celebrate Purim on the 15th of Adar.
This Treat was originally published on March 9, 2012.