Esther 9:29-31

Then Queen Esther, the daughter of Abihail, and Mordecai the Jew gave full written authority, confirming this second letter about Purim. Letters were sent to all the Jews, to the 127 provinces of the kingdom of Ahasuerus, in words of peace and truth, that these days of Purim should be observed at their appointed seasons, as Mordecai the Jew and Queen Esther obligated them, and as they had obligated themselves and their offspring, with regard to their fasts and their lamenting.