Maamar V'Kibel Hayehudim - Chapter 2
When G-d beheld that Satan's messengers were causing the Jewish people to sin and that the state of observance of Torah and mitzvos was constantly worsening, He had the archenemy and oppressor of the Jewish people, Haman, get Achashveirosh to issue various harsh decrees against the Jews.
Haman assembled kindred spirits who, like him, were rabid Jew haters, in order to decide when would be the best time of year to carry out the evil decree of annihilating - may it never come to pass - the Jewish people. He then went to Achashveirosh to receive his permission to carry out the slaughter.
Haman put together a cunning slander of the Jews. He was sure that his calumny would bear fruit and the king would approve his plan of annihilating the Jewish people. Haman was sure of the success of his evil decrees, for he knew how sinful the Jewish people were and that the "attribute of justice" would incite - G-d forbid - against the Jewish people.
Indeed, this was the inner and more profound meaning of Haman's slander; that Satan, the primordial serpent, incited before King Achashveirosh, [i.e., G-d, known as Achashveirosh because ] He that the first [in Hebrew reishis] and the last [in Hebrew achris] are His, as the verse states: "I am first and I am last."
Haman slandered the Jews, saying: "There exists [in Hebrew yeshno] one [in Hebrew echod] nation, scattered and dispersed among the nations, whose laws differ from the laws of all other nations, and the king's laws they do not obey."
[In spiritual terms the complaint of Satan was as follows:] "There exists - yeshno - one nation...." The word yeshno [comes from the Hebrew word yesh which] means might and will.
Satan slandered the Jews saying that the might and will of the Jews which was given to them by G-d, for which reason they are called "one nation" as the verse states: "And who is like Your people Israel, the one nation on earth,"[ was not being properly utilized.]
The Jewish people have a will so strong and power so mighty that they are able - through their study of Torah, performance of mitzvos and good character traits - to draw down the One G-d even into this material world, that even in this world G-d's unity be recognized and that G-dliness be perceived and felt.
But they, said Satan, the one nation that was imbued by the One G-d with these mighty powers, are "scattered and dispersed among the nations" - they utilize their G-d given gifts and talents for various "national" affairs, i.e. mundane matters.
[Furthermore said Satan] "...whose laws differ from the laws of all other nations...."
Jews are different than all other nations. Every nation has its own physical and spiritual life style which they adhere to and do not change. This is not the case with the "one nation... whose laws differ from the laws of all other nations...." They are ready and willing to do and change anything and everything - G-d forbid - in order that they be similar to all other nations. This is due to the fact, he continued, that "...the Kings laws," i.e. G-d's laws, the King of the world, "they do not obey." It was of such calumny that Ravah said: "No one can approach Haman's ability to speak ill [of the Jewish people]."
Haman successfully incited against the Jews [before the King,] and Jews in all Achashveirosh's countries felt the great travails brought upon them by Haman's decrees. The painful affliction of the decrees aroused within a segment of Jewry a brokenheartedness that led to repentance.
This spirit of contrition aroused the wrath of the heretical leaders. They began consoling the Jews in a variety of ways.
They tried to prove to them that the harsh decrees were not so bad after all, but rather stemmed from the kingdom's sincere desire to have all manner of good showered upon the Jewish people.
This goodness, the heretics assured the Jews, would come about when Jews applied themselves diligently to labor and craft.
These leaders went on to say that Jews should not believe in G-d's salvation through His redemption of them from exile. On the contrary, they maintained that now more than ever it was of utmost importance to become one with the inhabitants of the land.
By dint of the words and deceitful actions of the evil leaders, Satan managed to convince the Jews that they regress in their brokenheartedness and repentance and in a variety of ways further their relationships with the land's inhabitants.
The Jews continued to sin, and Jewish afflictions increased accordingly.
Nothing came about from the empty promises of the heretical leaders except for profanation of holiness, eating of non-kosher food and other sins. All the while the Jews' torment and pain continued to increase.
However, "And Mordechai knew all that was happening." Says the Yalkut: Mordechai knew how to heal the torment; he knew which sins caused the afflictions, and he knew the healing measures.
Mordechai assembles all the Jewish people and tells them that all their afflictions stem from their straying down the evil paths of profaning the Shabbos, eating forbidden foods and other sins. Mordechai arouses the Jews to a tremendous awakening to repentance and assures them of the coming redemption. The Jewish people obey Mordechai's call to repentance, and they steadfastly believe in the coming redemption.
This, then, is the meaning of the verse "And the Jews took upon themselves [to do] that which they had begun to do."
They became pious and performed Torah and mitzvos with true Jewish self-sacrifice. A year later the redemption came, and within four years the Holy Temple was rebuilt.
Herein lies the awesome might of repentance.
Jews were, during that trying period, surrounded by opponents of their religion. They were also under the influence of people that denied G-d and hated Judaism - people who scoffed at Torah and mitzvos and mocked the righteous Mordechai and members of the Sanhedrin.
[All this notwithstanding], they were still able through repentance to attain a most lofty spiritual level, a level similar to that attained during the most holy time of receiving the Torah.
G-d accepted their true repentance, their regrets for past misdeeds and their good resolutions for the future to be loyal to Torah and mitzvos. G-d rains good fortune upon them through the miracle of Purim and the Jewish people are favored with the redemption.
Explains that the corrupting words of the heretical leaders brought upon the Jewish people Haman's decrees and the resulting travails.
Haman is empowered by Satan's calumny of the Jews, that they, the chosen people, use their G-d given powers only for mundane matters, and [Satan] exerts himself to the utmost to see to it that the Jewish people become unified with the laws of the nations and torn asunder from G-d's laws.
Mordechai's call to repentance affects the Jewish people. Their total self-sacrifice for Torah and mitzvos leads to the miracle of Purim.