Esther 9:27-29

Amplified Bible

²⁷ the Jews established and made it a custom for themselves and for their descendants and for all who joined them, so that they would not fail to celebrate these two days as it was written and at the appointed time annually. ²⁸ So these days were to be remembered and celebrated throughout every generation, every family, every province and every city; and these days of Purim were not to cease from among the Jews, nor their memory fade from their descendants.

²⁹ Then Queen Esther, the daughter of Abihail, with Mordecai the Jew, wrote with full power and authority to confirm this second letter about Purim.