'Of The Month' in the Bible

The Jews who were in Susa also gathered together on the fourteenth day of the month of Adar and killed three hundred men in Susa, but they did not lay their hands on the plunder.

This was done on the thirteenth day of the month of Adar, and on the fourteenth day they rested and made it a day of feasting and rejoicing.

Therefore the Jews of the villages, who live in the rural [unwalled] towns, make the fourteenth day of the month of Adar a holiday for rejoicing and feasting and sending choice portions of food to one another.

obliging them to celebrate the fourteenth day of the month of Adar, and the fifteenth day of the same month, annually,