Therefore, the unfortified Yehudim in the unfortified cities made the
fourteenth day of the month of Adar [a day of] joy, feasting, and
holiday, and from sending gifts a man to his fellow.
According to Rashi, quoting the Talmud (Megillah 2b) “unfortified cities” are those that were not surrounded by walls in the days of Yehoshua.
The Ziv HaMinhagim writes that this definitely includes only Yerushalayim. There is a doubt regarding Ashdod, Ashkelon, Beit Sha’an, Gush Khaloav, Hebron, Haifa, Tiberias, Jaffa, Lod, Gaza, Acco, Safed, Ramleh, and Shechem.
R’ Ovadya of Bartenura explains that the times of Yehoshua are the reference point for the definition of walled cities in order to remind us of the root hatred of Amalek is their attacking us when we were leaving Mitrzrayim, when they battled Yehoshua.
The Sfas Emes adds that, by recalling Yerushalayim, we remember that the purpose of Purim was the rebuilding of the Beis HaMikdash.
6. And the king said to Esther in the drinking party, “What is your request and it will be given you, and what is your petition? Until half of the kingdom, and it will be done.”
The Ben Ish Chai writes that this is not the first wine party in Megillas Esther. In fact, after Haman and Achashverosh sign the decree meant to threaten Jewish existence, the verse (Esther 3:15) writes that they drank together. At that party something happened that this party will help to undo. Besides this, the verse there says that the city of Shushan was left bewildered. Among the reasons for this confusion is that the Jews were not privy to the content of the decree. They were left unclear as to the veracity of the inevitable rumors that this decree intended their demise. The Ben Ish Chai writes that this party, providing the tikkun to the previous party in the manner of “zeh l’umas zeh,” will leave no confusion.
The Kotzker Rebbe writes that we are all supposed to remember that H-Shem listens to our requests not only when we are praying in a holy environment, but also when we are sitting at a table, eating and drinking in the measured way in which we are instructed. This is why H-Shem, the King in our verse tells Esther, who represents the Jews, that He will do what she requests. This is one reason why we request in Birkas HaMazon a number of things besides sustenance.
The Dubno Maggid adds that King David unified his requests with his goals (see Tehillim 27:4). The Talmud (Avodah Zara 19a) says that one should do mitzvos for their own sake. This is what Dovid was doing. This is particularly relevant in the area of prayer because the Talmud (Brachos 20a) calls Yerushalayim “the hill towards which all mouths are directed.” We all have different mouths – or requests – but they are all for the same goal. Everything we want should be for the sake of our personal relationships with H-Shem.