Between Purim and Pesach
The 13th of Nisan, not the 13th of Adar, is the date that holds the key to understanding the Megillah. On the 13th of Nisan, Haman chose and announced the 13th of Adar as the date to exterminate the Jews of the Persian empire. The contrast with the Torah’s first 13th of Nisan, in the year of the Exodus, could not be sharper or more bitter. That year, the 13th of Nisan brought the Israelites one day closer to the inevitable and overwhelming redemption God had been fashioning, that took place the very next day, on the 14th. In the Megillah, the Jews instead learn of their imminent destruction, to occur on a date chosen by chance, not God.