Esther 8:3-8
English Standard Version
3 Then Esther spoke again to the king. She fell at his feet and wept and pleaded with him to avert the evil plan of Haman the Agagite and the plot that he had devised against the Jews. 4 When the king held out the golden scepter to Esther, Esther rose and stood before the king. 5 And she said, “If it please the king, and if I have found favor in his sight, and if the thing seems right before the king, and I am pleasing in his eyes, let an order be written to revoke the letters devised by Haman the Agagite, the son of Hammedatha, which he wrote to destroy the Jews who are in all the provinces of the king. 6 For how can I bear to see the calamity that is coming to my people? Or how can I bear to see the destruction of my kindred?” 7 Then King Ahasuerus said to Queen Esther and to Mordecai the Jew, “Behold, I have given Esther the house of Haman, and they have hanged him on the gallows, because he intended to lay hands on the Jews. 8 But you may write as you please with regard to the Jews, in the name of the king, and seal it with the king's ring, for an edict written in the name of the king and sealed with the king's ring cannot be revoked.”
Esther 9:18-23
English Standard Version
18 But the Jews who were in Susa gathered on the thirteenth day and on the fourteenth, and rested on the fifteenth day, making that a day of feasting and gladness. 19 Therefore the Jews of the villages, who live in the rural towns, hold the fourteenth day of the month of Adar as a day for gladness and feasting, as a holiday, and as a day on which they send gifts of food to one another.
The Feast of Purim Inaugurated
20 And Mordecai recorded these things and sent letters to all the Jews who were in all the provinces of King Ahasuerus, both near and far, 21 obliging them to keep the fourteenth day of the month Adar and also the fifteenth day of the same, year by year, 22 as the days on which the Jews got relief from their enemies, and as the month that had been turned for them from sorrow into gladness and from mourning into a holiday; that they should make them days of feasting and gladness, days for sending gifts of food to one another and gifts to the poor.
23 So the Jews accepted what they had started to do, and what Mordecai had written to them.