Esther 9:25-27

New Living Translation

²⁵ But when Esther came before the king, he issued a decree causing Haman’s evil plot to backfire, and Haman and his sons were impaled on a sharpened pole. ²⁶ That is why this celebration is called Purim, because it is the ancient word for casting lots.

So because of Mordecai’s letter and because of what they had experienced, ²⁷ the Jews throughout the realm agreed to inaugurate this tradition and to pass it on to their descendants and to all who became Jews. They declared they would never fail to celebrate these two prescribed days at the appointed time each year.