Megila
Therefore, the Jewish villagers who live in open towns make the fourteenth day of the month of Adar [a day of] joy and feasting and a festive day, and of sending portions to one another.
And Mordechai inscribed these things and sent letters to all the Jews who were in all the provinces of King Ahasuerus, both near and far: to enjoin them to make the fourteenth day of the month of Adar and the fifteenth day thereof, every year.
As the days when the Jews rested from their enemies, and the month that was reversed for them from grief to joy and from mourning to a festive day, to make them days of feasting and joy, and sending portions one to another and gifts to the poor.
And the Jews took upon themselves what they had commenced to do and what Mordechai had written to them. . . .
Consequently, these days are recalled and observed in every generation: by every family, every province, and every
city.
And these days of Purim shall never cease among the Jews, and the memory of them shall never perish among
their descendants.
Halachot Gedolot, End of Hilchot Megilah
The day of Purim is as great as the day on which the Torah was given.
talmud
The verse states, “And they stood under the mount.” Rabbi Abdimi ben Hama ben Hasa said: This teaches that the Holy One, blessed be He, overturned the mountain upon them like an [inverted] cask and said to them, “If you accept the Torah, all is well; if not, there shall be your burial.” Rabbi Acha ben Jacob observed: This furnishes a strong protest against the Torah. Said Raba: Yet, even so, they reaccepted it in the days of Ahasuerus, for it is written, “[The Jews] confirmed and took upon them [etc.]”; [i.e.,] they confirmed what they had accepted long before.
TORAH OR
This is why “[G-d] overturned the mountain upon them like a cask”; as in the verse, “His right hand embraces me,” it implies a degree of expression of G-d’s supernal love for the Jewish people. . . . This love “embraces” the collective Jewish people, [as when one hugs another person,] surrounding him from all sides, even the back, so that he cannot move away and is compelled to stand there, facing him. In other words, because of G-d’s supernal love, a love awakened within the souls of the Jewish people, uplifting them to the point where they would declare, “We will do [and we will obey]!” . . . Revealing this light of love from above—such as it says, “I loved you [said G-d]”—awakens a corresponding love from below to above; this is the elevation of the Jewish collective, the expiration of their souls toward Him. . . . This is the meaning of “overturning of the mountain”; it suggests the supernal love, which is referred to as a “mountain.” It is likened to a “cask,” which suggests something that surrounds and overwhelms all worlds, a light so intense that it awakens a love within them.
Torah or
This, then, is the meaning of our sages’ statement, “This furnishes a strong protest against the Torah.” In other words, the feeling that stirred in their hearts to accept the Torah with such sacrifice and surrender that they declared, “We will do and we will obey,” was not entirely a result of their own choice and desire. Rather, it was on account of the revelation of G-d’s love from on high that inspired their reciprocal love to Him.
Had they apostatized, G-d forbid, nothing would have happened to them, for the decree only applied to Jews. Nevertheless, not one of them even entertained an outside thought, G-d forbid, and instead sacrificed their lives for G-d.
Notwithstanding all the challenges, the Jews accepted [the Torah] completely willingly in the days of Ahasuerus; they performed a collective act of self-sacrifice, on their own, totally unprompted by any supernal initiation in the form of a “Divine embrace.” After all, it was a time of spiritual concealment . . . Therefore, it was an organic, collective spiritual awakening from below. This is the meaning of the [Talmudic statement] that they then accepted [the Torah] completely willingly. . . .
At Matan Torah [the Giving of the Torah on Mount Sinai] they declared, “We will do and then we will obey,” and their souls expired every time G-d spoke. This indicates the state of self-nullification [bitul] and sacrifice they achieved, which made them worthy of the G-dly revelation that Matan Torah was.This same spiritual state of bitul was achieved in the days of Ahasuerus, only to a greater degree: At Matan Torah, this state of bitul was initiated from above and then reciprocated by the Jewish people, while in the days of Ahasuerus this state of bitul came from them, on their own initiative. Therefore, the spiritual flow that resulted came from an even higher place, so much so that the revelation of Matan Torah was only the “beginning,” relative to the spiritual light that came down on Purim, which is referred to as the [subsequent] and final “acceptance.” This is the meaning of the verse, “And the Jews accepted. . . .”