Esther 4:3; Esther 9:31

3 In each and every province where the command and decree of the king came, there was great mourning among the Jews, with fasting, weeping and wailing; and many lay on sackcloth and ashes.

31 to establish these days of Purim at their appointed times, just as Mordecai the Jew and Queen Esther had established for them, and just as they had established for themselves and for their descendants with instructions for their times of fasting and their lamentations.