'Twelfth' in the Bible

In the first month, the month of Nisan (Mar-Apr), in the twelfth year of King Ahasuerus, Haman cast Pur, that is, the lot, cast before him day after day [to find a lucky day to approach the king], month after month, until the twelfth month, the month of Adar (Feb-Mar).

Letters were sent by couriers to all the king’s provinces to destroy, to kill and to annihilate all the Jews, both young and old, women and children, in one day, the thirteenth [day] of the twelfth month, which is the month of Adar (March 7, 473 b.c.), and to seize their belongings as plunder.

on one day in all the provinces of King Ahasuerus, the thirteenth [day] of the twelfth month (that is, the month of Adar).

Now in the twelfth month (that is, the month of Adar) on the thirteenth day when the king’s command and edict were about to be executed, on the [very] day when the enemies of the Jews had hoped to gain power over them [and slaughter them], it happened the other way around so that the Jews themselves gained power over those who hated them.