Then Esther the queen, the daughter of Abihail, and Mordecai
the Jew, wrote with all authority
Strongly pressing the observance of this festival; before, Mordecai only recommended it, but now the queen gave a sanction to it, and laid her obligation on the Jews to observe it; perhaps some of the Jews were backward to it, or neglected to observe it, and therefore Esther and Mordecai joined in a letter to them, to press them to it; the Jewish chronologer F24 says, this was written the year following; the former Targum is, they wrote this whole volume, and the strength of the miracle, or set the miraculous deliverance in the strongest light, with this view,
to confirm this second letter of Purim;
that it might have its weight and influence upon them, to engage them to keep it, as the latter Targum adds; that when it was an intercalary year, they might not read the Megillah (or book of Esther) in the first Adar, but in the second Adar.
F24 Seder Olam Rabba, c. 29. p. 87.