To establish these days of Purim at their designated times, as Mordecai the Jew and Queen Esther had decreed for them, and as they had established for themselves and their descendants in regard to their times of fasting and lamentation.
NIV
To confirm that these days of Purim should be observed at their appointed times, as Mordecai the Jew and Queen Esther had commanded [the Jews], and as they had ordained for themselves and for their descendants in the matter of their fasts and their lamenting.
AMP
To confirm these days of Purim in their times appointed, according as Mordecai the Jew and Esther the queen had enjoined them, and as they had decreed for themselves and for their seed, the matters of the fastings and their cry.
KJV