Esther 9:31
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.
Cross-reference
Esther 9:27
Parallel
In Esther 9:27, the Jews first committed to keep Purim; here Esther and Mordecai officially confirm that commitment.
Esther 4:3
Parallel
In Esther 4:3, the Jews mourned and fasted; here those practices are commemorated in the Purim observance.
Esther 4:16
Parallel
In Esther 4:16, Esther calls for a fast; here the institution of Purim includes remembrance of that fasting and lamentation.