וַיְהִ֨י אֹמֵ֜ן אֶת־הֲדַסָּ֗ה הִ֤יא אֶסְתֵּר֙ בַּת־דֹּד֔וֹ כִּ֛י אֵ֥ין לָ֖הּ אָ֣ב וָאֵ֑ם וְהַנַּעֲרָ֤ה יְפַת־תֹּ֙אַר֙ וְטוֹבַ֣ת מַרְאֶ֔ה וּבְמ֤וֹת אָבִ֙יהָ֙ וְאִמָּ֔הּ לְקָחָ֧הּ מָרְדֳּכַ֛י ל֖וֹ לְבַֽת׃
And (Mordechai) brought up Hadassah, (Hadassah) is Esther, his uncle’s daughter; for she had neither father nor mother, and the maiden was of beautiful form and fair to look on; and when her father and mother were dead, Mordechai took her for his own daughter.
R. Eliezer's opinion, that Purim is observed in Adar I, is logical, for there is a principle that one should never pass up an opportunity to perform a mitzvah. But why would R. Shimon b. Gamaliel hold that Purim is delayed until Adar II?! R. Tabi says that R. Shimon b. Gamaliel wanted the redemption of Purim to be close to the redemption of Pesach. Therefore, they should be observed in adjacent months.
אמר רב יהודה בריה דרב שמואל בר שילת משמיה דרב כשם שמשנכנס אב ממעטין בשמחה כך משנכנס אדר מרבין בשמחה
Rav Yehuda son of Rav Shemuel son of Sheilat said in the name of Rav: Just as when Av enters we decrease our happiness, when Adar enters we increase our happiness.
ימי נסים היו לישראל פורים ופסח:
These were days of miracles for the Jews: Purim and Passover
שׁוֹאֲלִין בְּהִלְכוֹת פֶּסַח קֹדֶם לַפֶּסַח שְׁלֹשִׁים יוֹם.
We begin to study the laws of Passover 30 days before Passover
זוהי גם הסיבה לכך שלא מוזכר בכל המגילה אף שם משמות הש“י, כיון שאם היה כתוב בגלוי שמו של הקב“ה היתה זו יציאה מגדר הטבע למעל הטבע, וזה כבר נוגע לפסח. אך פורים מגלה לנו שכל דבר בתוך הטבע החשוך זוהי פיסגת האהבה. ...
היכן רואים יותר אהבה בפורים או בפסח? בחג הפסח הרים אותנו הקב“ה מעל העולם, אבל בפורים אנו מגלים את הקב“ה בכל נקודה ונקודה של טבע.
Rabbi Shimshon Pinkus, Purim, Ch. 2 –
This is also the reason for which none of the names of God are mentioned in Megillat Esther. Since if His name would be written explicitly, this would constitute a departure from the natural into the supernatural – which is applicable to Passover. Purim, however, reveals that each aspect within nature is imbued with the love of God …
Where does one find more intense love: in Passover or in Purim? On Passover God raised us over the entire world, but on Purim we discover God in every nook and cranny of the natural world.
אסתר מן התורה מנין (דברים לא, יח) ואנכי הסתר אסתיר
Where is Esther indicated in the Torah?
In the verse,"And I will surely hide [astir] my face." (Devarim 31:18)
אמר רב הונא אמר רב משום רבי מאיר וכן תנא משמיה דר' עקיבא לעולם יהא אדם רגיל לומר כל דעביד רחמנא לטב עביד
Rab Huna stated that Rab said in the name of R. Meir, (and it has been similarly taught in the name of R. 'Akiba) : A man should always accustom himself to say, "Whatever the All-merciful does, He does for the best."
Rabbi Yanki Tauber, Chabad.org – Costumes and the joy of Purim: When Nothing is as it Seems
Why do we disguise ourselves on Purim? Because on Purim nothing is as it seems. Was the killing of Vashti simply one of those things that happen when a debauched Persian emperor gets drunk? Was it just coincidence that Mordechai happened to overhear a plot to kill the king? Did Achashveirosh choose Esther to be his queen because she happened to be the most beautiful woman in the empire? Was it plain bad luck for bad Haman that he happened to visit Achashveirosh just when the king was having Mordechai’s heroic deed read to him? Was it Esther’s charm and Achashveirosh’s flippancy that made the king suddenly hang his favorite minister? Purim was instituted because the Jewish people at the time understood that it was God Himself Who did all of the above, to save His people. He was just disguising Himself as a Persian palace soap opera.
When God took the Children of Israel out of Egypt on Passover, the entire neighborhood, from Giza to Gaza and from Memphis to Mesopotamia, resonated with the miracles wrought by the God of the Hebrews. When a small jug of oil burned for eight days on Chanukah, the most skeptical Hellenist saw that it was an act of God. Purim (“lots”) is unique in that the most miraculous of salvations was shrouded in the garments of nature, luck and coincidence. God was hidden and remained hidden – His name does not once appear in the entire Megillah! Not paradoxically, Purim is also the most joyous festival of the Jewish calendar. It’s great to celebrate miracles, but how often does a miracle come your way? Far more exhilarating is the realization that nothing is as it seems, that God is always pulling the strings, even when things seem to be “just happening.”