Esther 3:7, 13
In the twelfth year of King Xerxes, in the first month, the month of Nisan, the pur (that is, the lot) was cast before Haman to determine a day and month. And the lot fell on the twelfth month, the month of Adar. . . .

Esther 8:12
The single day appointed throughout all the provinces of King Xerxes was the thirteenth day of the twelfth month, the month of Adar.

Esther 9:1, 15, 17, 19, 21
On the thirteenth day of the twelfth month, the month of Adar, the king's command and edict were to be executed. On this day the enemies of the Jews had hoped to overpower them, but the tables were turned and the Jews overpowered those who hated them. . . .