Esther 9:27-28

the Jewish people set up this custom. They and their descendants and all those who join them are always to celebrate these two days every year. They should do it in the right way and at the time Mordecai had ordered them in the letter. These two days should be remembered and celebrated from now on in every family, in every state, and in every city. These days of Purim should always be celebrated by the Jewish people, and their descendants should always remember to celebrate them, too.