Besides stressing that the verse mention that the gallows were prepared “for him,” R’ Shlomo Kluger in Ma’amar Mordechai points out that in order to be consistent with Zeresh’s advice earlier (Esther 5:14), the verse should have written “asher asa lo” (“that he made for him”) instead of “asher heichin lo” (“that he prepared for him”).
The Talmud (Megillah 16a) explains that the gallows Haman had built were prepared in the ironic sense that they would unintentionally be used for his own hanging.
The Vilna Gaon explains that, as opposed to something whose purpose changes, the gallows were never meant for Mordechai at all, and were always for Haman. Some things historically had an intended purpose, and were then appropriated for some other use. T.N.T., for instance, was meant to be used solely for construction. Its being adopted for use in war so traumatized its inventor, Alfred Nobel, that he developed the Nobel Peace Prize for those who allegedly bring peace to the world. These gallows, by contrast, from their inception, were always intended for Haman’s downfall.
R’ Dovid Feinstein explains that the gallows had to be a perfect fit for Haman, since he and his sons all fit on the same gallows (see Targum Sheini to Esther 9:14). See attached chart.
According to the opinion that the gallows were made from the beams of the Beis HaMikdash, the Ben Ish Chai asks how Mordechai could have the right to use them as he will when he hangs Haman (Esther 7:10) since he would thereby desecrate these holy objects (Pirkei D’Rebbe Eliezer 50). However, answers the Ben Ish Chai, Haman’s using the beams first took away their sanctity, preparing the beams for use in his own death.
Using Newtonian physics, the Maharal points out that if an object that is thrown at a wall drops straight down upon impact, this shows the amount of force applied by the thrower. However, if the object bounces back upon impact, this means the thrower applied more force, and it was only the wall’s strength that kept the object from its intended place. Similarly, in yet another example of mida kineged mida, what happened to Haman (and his sons) reflects the vehemence with which they planned to dispatch Mordechai.
According to R’ Yehonason Eibshutz in Yaaros Dvash, Haman intended hang a completely different “him” – the king. After all, Haman had planned a conspiracy to take over the monarchy.
On a Halachic point, the Chasam Sofer notes that hachana (“preparation”) usually implies in the legal world preparing for the next days. In this case, where Haman prepared the gallows earlier that morning, why is this hachana for the same say? He answers that hachana for gentiles does not need to be for the next days since the Talmud describes them as “holech achar hayom,” that they follow a solar schedule, controlled by the sun.
The Belzer Rebbe adds that Halacha recognizes the need for mitzvos to have hachana; this is not true for sins. For example, consider how much planning you needed to put into learning right now, versus how much planning you would have needed to waste your time in front of a tv or computer screen, instead. Therefore, the gallows must have been for Haman since killing out the nation of Amalek is a mitzvah (Rambam, Mishneh Torah, Hilchos Melachim 6:4).
According to R’ Eliezer of Worms, the verse use the word “parashas” (“chapter”) to describe Haman’s meeting with Achashverosh in order to emphasize that this event was not just talk – a financial exchange took place, giving the event legal significance and legally binding consequences.
In fact, as the Divrei Shaul points out, Mordechai was communicating to Esther the fact that Achashverosh could not be easily bought off, since Haman had already given/ offered him money (see above 3:11).
As R’ Dovid Feinstein notes, Achashverosh’s refusal to accept the bribe only stresses the ferocity of his hate for the Jews, making this a very serious threat to Jewish existence, indeed. Convincing Achashverosh to change his mind would require nothing short of a miracle.
Parenthetically, According to Yaaros Dvash, the fact that Achashverosh refused the money was covered up by Haman in an attempt to deny people the opportunity to intercede on behalf of the Jews.
The Chasam Sofer writes that Mordechai’s giving the details of this entire episode here served a vital purpose later. In fact, Esther uses this event in detail to convince the king to save the Jews from Haman’s decree. In the Chasam Sofer’s view of the events, Achashverosh refused Haman’s money (see 3:11 above) because he reasoned that killing such a people was a worthwhile responsibility of his, and taking payment for this would be unethical. In Achashverosh’s mind, Haman’s offer and and his refusal were secret. Since Mordechai’s knowledge of this came through a Ruach HaKodesh-like dream, Mordechai kept the information under wraps to be used later, if necessary. Once Esther tells Achashverosh that her people had been “sold” (see 7:4 below), Achashverosh begins to suspect that Haman had libelously spread the rumor that he had, indeed, accepted Haman’s payment. Therefore, he responds by asking who would do such a thing (see 7:5 below). It seems improbable that Achashverosh had forgotten the entire incident, so he is asking who would spread such a rumor.
The Brisker Rav interprets the word “parasha” as being related to “lihafreesh” (“to set aside”). In his view, Mordechai was informing Esther of the money that was set aside, or designated for the purchase of killing out the Jews. Such money was legally binding, and eventually, Achashverosh’s only way out of the deal would have be to kill the “buyer” – Haman.
Alshich uses Rashi’s seemingly simple explanation that “parsha” means explanation to mean that Mordechai related all of the details of Haman’s and Achashverosh’s meeting, including the mystical interpretations for the reasons Haman had to offer 10,000 loaves of silver.
Finally, the Sfas Emes translates “parashas” to mean “sum,” emphasizing Haman’s generosity in contributing towards the kingdom. In view of the concept of “zeh l’umas zeh,” the Jews need to be generous with charity in order to counterbalance the generosity of our enemies.