Esther 9:18-23
(NKJV)
[18] But the Jews who were at Shushan assembled together on the thirteenth day, as well as on the fourteenth; and on the fifteenth of the month they rested, and made it a day of feasting and gladness.
[19] Therefore the Jews of the villages who dwelt in the unwalled towns celebrated the fourteenth day of the month of Adar with gladness and feasting, as a holiday, and for sending presents to one another.
[20] And Mordecai wrote these things and sent letters to all the Jews, near and far, who were in all the provinces of King Ahasuerus,
[21] to establish among them that they should celebrate yearly the fourteenth and fifteenth days of the month of Adar,
[22] as the days on which the Jews had rest from their enemies, as the month which was turned from sorrow to joy for them, and from mourning to a holiday; that they should make them days of feasting and joy, of sending presents to one another and gifts to the poor.
[23] So the Jews accepted the custom which they had begun, as Mordecai had written to them,