Esther 9:16-18

9:16 The rest of the Jews who were throughout the provinces of the king assembled in order to stand up for themselves and to have rest from their enemies. They killed seventy-five thousand of their adversaries, but they did not confiscate their property. 9:17 All of this happened on the thirteenth day of the month of Adar. They then rested on the fourteenth day and made it a day for banqueting and happiness.

The Origins of the Feast of Purim

9:18 But the Jews who were in Susa assembled on the thirteenth and fourteenth days, and rested on the fifteenth, making it a day for banqueting and happiness.