Esther 9:20-23

Mordecai recorded these events, and he sent letters to all the Jews throughout the provinces of King Xerxes, near and far, to have them celebrate annually the fourteenth and fifteenth days of the month of Adar as the time when the Jews got relief from their enemies, and as the month when their sorrow was turned into joy and their mourning into a day of celebration. He wrote them to observe the days as days of feasting and joy and giving presents of food to one another and gifts to the poor. So the Jews agreed to continue the celebration they had begun, doing what Mordecai had written to them.