21. To establish on them to make the doing of the fourteenth day of the month of Adar and the fifteenth day of it in every year and year.
The Ginzei HaMelech notes that the word, kayam (“established”) is used ten times in Megillas Esther. This parallels the Ten Commandments in order to demonstrate that Purim is an extension of the fulfillment of the Torah, not an addition to it.
In Chiddushei HaLeiv, R’ Hanoch Leibowitz quotes the Talmud Yerushalmi (Megillah 1:5) which says that 85 elders, among whom were 30 or more prophets, struggled with fitting the addition of Purim with the idea behind the words (Vayikra 27:34) “these are the mitzvos.” which do not allow for adding new mitzvos. R’ Leibowitz notes that these wise people were said to “struggle” over these words because that is what great leaders and Halachic deciders to – they struggle. He quotes the Chut HaMeshalesh (8) of R’ Chaim Volozhinner in which the author writes that he struggled to free a particular agunah (“married woman whose missing husband had not granted her a divorce”) to remarry. R’ Leibowitz notes that, beyond the intellectual logic and knowledge to figure out a law, a posek needs to have an overwhelming desire to help others, and to struggle for them, and this is why the verse stresses that such a leader – Mordechai – established these holidays for his flock.
In his introductory comments on the Talmudic tractate Megillah, the Ramban explains that the idea behind sending the books near and far means that they were sent through the entire expanse – from Hodu to Cush (Esther 1:1) – of Achashverosh’s kingdom.
Me’am Loez suggests that they were even sent to other countries.
The Dena Pishra explains that since Mordechai’s goal was to create a feeling of achdus (“unity”), he even wanted to reach those Jews whose lack of faith and subsequent fear motivated them to flea battle.
Rav Schwab, however, understands “close” as those Jews who were living in Shushan and celebrating on the 14th of Adar, whereas “far” refers to those Jews who returned to Eretz Yisroel and celebrated Shushan Purim on the 15th of Adar in the only place where one must certainly do so – the holy city of Yerushalayim.
The Sha’ar Yissachar writes that the books were sent near and far so no Jew could ever devise the excuse that they are too far from holiness. Rather, the near and far have equal access to the holiness that emanates from Purim.
Keser Shem Tov quotes that Talmudic (Megillah 17a) rule that Megillas Esther on Purim must be read as written, and not backwards. The Keser Shem Tov then wonders why anybody would think to read it backwards. He posits that the Talmud means that nobody should ever consider the Purim story as some ancient, historic event without real relevance to our lives.
And Mordechai wrote these things and sent books to all of the Yehudim
in all of the states of King Achashverosh, the near and the far.
Malbim says that what Mordechai wrote were the details of what occurred, since he was concerned that Jews outside of Shushan knew very little about the miraculous success of the Jews of Shushan.
According to Rashi, what Mordechai wrote is the content of Megillas Esther, exactly as it appears today.
The Ibn Ezra wrote down the reason for the previously mentioned joy.
Pirkei d’Rebbe Eliezer writes that Mordechai wrote this down as the head of the Sanhedrin.
The Vilna Gaon explains that this means that he wrote the Halachic details of how to properly commemorate Purim, with what can and cannot be done on this day.
R’ Dovid Feinstein emphasizes that Mordechai is making the changes for the holiday that the Jews had accepted upon themselves spontaneously.
R’ Elisha Gallico notes that it is so important to remember the real source of Purim, there are two readings of Megillas Esther every Purim. This is why Moredechai did not make Purim an actual Yom Tov in order to allow the Jews to perform the other mitzvos of the day.
The Oznei Yehoshua notes that if we had Purim without its rules, we would end up having an empty, meaningless holiday. As it stands, Purim is the epitome of giving in the Jewish community.