1) AGADAH: THE ROLE OF CHILDREN ON PURIM
QUESTION: The Gemara relates that when Haman came to take Mordechai to dress him in the royal garments and lead him on the royal horse, he found Mordechai sitting in front of the Chachamim, teaching them the laws of Kemitzah (the handful of flour offered for the Korban Minchah). The same incident is recorded in the Midrash (Esther Rabah 10:4).
The Midrash relates further that the Chachamim who learned before Mordechai were children. According to the Midrash, this was Haman's second visit to Mordechai. He had come looking for Mordechai on the previous night, after he had built the gallows upon which he intended to hang Mordechai. On the previous night he found Mordechai seated with 22,000 children before him, dressed in sackcloth and studying Torah. The children had been fasting for three days. Haman ordered them shackled in iron chains and appointed guards to watch them. He declared, "Tomorrow I will kill these children first and then hang Mordechai!" All of the children burst out in tears and their cries rose to the heavens. Two hours into the night, Hash-m hearkened unto their cries, and "at that moment, Hash-m took the decrees [that He had written to punish the Jews] and tore them up" (Esther Rabah 9:4).
Another Midrash (Esther Rabah 7:13) relates that it was a group of children who first encouraged Mordechai with an omen from above that his prayers would be answered.
The Midrash is clearly making a point that it was the children who predicted, and brought about, Haman's downfall. This is reflected in the verse that says, "Through the mouths of children and babes You have shown Your power to the oppressors, bringing an end to a vengeful enemy" (Tehilim 8:3).
Why did children play such a significant role in the miracle of Purim?
ANSWER: Children have a special power to protect the entire Jewish people from Haman in particular and from Amalek in general. The Gemara in Bechoros (5b; see Rashi there) teaches that Amalek first attacked the Jews only because "they weakened their hands from [studying] the words of the Torah." Only when the Jewish people corrected this weakness were they able to conquer Amalek. Similarly, Haman succeeded in passing his evil decree only because the Jews "were lazy in the study of Torah" (Megilah 11a), and it was only in the merit of the children's pure Torah learning that the Jewish people were saved.
Jewish children ensure the continuity of the study of Torah. According to the Midrash (Shocher Tov 8; Shir ha'Shirim Rabah 1:4:1, see also Shabbos 33b), our children are our "guarantors" that we will study the Torah. Children learn Torah in the purest manner possible, since "the breath (speech) of one who has not sinned cannot be compared to that of one who has sinned" (Shabbos 119b).
At the time of Purim, the children -- who had not yet accomplished their task of perpetuating the Torah for future generations -- were threatened along with the rest of the nation by Haman's evil plot. When the children, led by their bold mentor, Mordechai, strengthened themselves in the study of Torah, the entire Jewish people merited to be saved from the hands of the enemy. The redeemed nation was now prepared to accept the Torah anew (Shabbos 88a, "Kiyemu v'Kiblu").
This explanation for the central role of children in the miracle of Purim lends clarity to the words of TOSFOS later in Megilah. The Mishnah later (19b) quotes Rebbi Yehudah who states that a minor may read the Megilah for an adult on Purim.
Why may a minor read the Megilah for an adult? In the case of all other Mitzvos, a minor cannot exempt an adult from his obligation to perform the Mitzvah because the minor's obligation to perform the Mitzvah is merely educational (Chinuch) and is secondary to the adult's obligation. Why is the Mitzvah of reading Megilas Esther different from all other Mitzvos?
TOSFOS (24a, DH Aval) addresses this question. Tosfos explains that when the Chachamim instituted the Mitzvah of reading the Megilah, they obligated minors along with adults because "children, too, were included in the miracle" of Purim, the same reason for which women are obligated to read the Megilah (4a). Since a minor's obligation in the case of the Mitzvah of Megilah is not merely a secondary obligation due to Chinuch but rather the identical obligation that applies to an adult, a minor may read the Megilah for an adult according to Rebbi Yehudah.
The Rishonim give two explanations for the Gemara's intention when it says that women are obligated to read the Megilah "because they were also included in the miracle." According to one explanation, Haman's decree to annihilate the Jewish people included both men and women (Esther 3:13). Since the miracle of Purim saved the lives of the women just as it saved the lives of the men, it is appropriate that women proclaim their appreciation for the salvation by reading the Megilah every year. This logic clearly applies to children as well.
According to the second explanation, "they were also included in the miracle" means that on Purim a woman was the primary agent for the Jews' salvation. Esther risked her life and persuaded the king to intervene on the Jews' behalf, and she inspired the nation to fast and repent. In recognition of her role in bringing about the miracle of Purim, the Chachamim included all women in the obligation to read the Megilah on Purim.
How does this explanation for "they were also included in the miracle" apply to children? In what way were children instrumental in bringing about the rescue from Haman's decree?
According to the Midrashim mentioned above, children indeed played a pivotal role in bringing about the salvation of Purim, and thus they have the same obligation to read the Megilah as adults.
This also explains the widespread custom cited by the REMA (OC 690) in the name of the AVUDRAHAM and ORCHOS CHAYIM. The Rema writes, "It was once customary for children to draw a picture of Haman or to write the name 'Haman' on sticks and stones and to clap them together so as to erase his name, in the spirit of the verse, 'You shall erase every trace of Amalek...' (Devarim 25:19). This eventually evolved into the children's present custom of banging [at the mention of] Haman when the Megilah is read publicly." Perhaps it was the practice of children to demonstrate the eradication of Haman by erasing his name from stones and by protesting the mention of his name, because it was they who brought about his downfall! (M. Kornfeld)
2) THE TIMING OF THE THREE-DAY FAST
OPINIONS: The Gemara relates that Haman's downfall was due to the merit of the fasting and repentance of the Jewish people. The Gemara says that after Mordechai was given royal honor by Haman at the orders of the king, Mordechai returned to his fasting and sackcloth. Later that day, Haman was killed.
(a) RASHI proves that the three-day fast decreed by Esther was observed on the fourteenth, fifteenth, and sixteenth of Nisan, because Mordechai was still fasting after he was led by Haman on the royal horse. The Gemara here relates that on the day that Haman came to take Mordechai to dress him in the royal garments and lead him on the royal horse, he found Mordechai teaching the laws of the Korban ha'Omer to the Chachamim. That day must have been the sixteenth of Nisan, the day on which the Korban ha'Omer was offered in the Beis ha'Mikdash. Later that day, Haman was hanged on his own gallows.
(b) The Midrashim, however, teach that the fast was observed on the thirteenth, fourteenth, and fifteenth of Nisan (Esther Rabah 8:7, Pirkei d'Rebbi Eliezer #50). The fast ended on the fifteenth of Nisan, and on that night (the eve of the sixteenth) "the slumber of the king was disturbed" and the prayers of the Jews were answered. Both the Midrash and the Gemara agree that the salvation occurred on the day on which the Omer was offered (Midrash Esther Rabah 10:4; see CHESHEK SHLOMO here).
(The RASHASH (15a), in fact, sheds doubt on Rashi's interpretation of the Gemara and suggests that the Gemara here also means that the public fast ended on the fifteenth and not on the sixteenth. The reason why Mordechai was still fasting after he was led around on the horse was because it is the practice of the righteous to continue the fast past its limit until their prayers are answered, as the Midrash (Esther Rabah 10:6) explicitly says.)
(c) The TARGUM apparently follows a third approach. According to the Targum (Esther 6:1), the night during which the king's slumber was disturbed was the eve of the fifteenth of Nisan, the same night on which Hash-m killed the firstborn of the Egyptians many centuries earlier. (This may be the intention of the author of "va'Yehi ba'Chatzi ha'Lailah," a Piyut recited after the Seder on Pesach night, who writes, "You began [Haman's] defeat by disturbing [the king's] sleep -- at night," a reference to the night on which Hash-m killed the firstborn of Egypt.) The Targum apparently disagrees with the Gemara's statement that the merit of the Korban ha'Omer brought about the salvation (and thus the salvation did not occur on the sixteenth, but on the fifteenth).
However, the Targum's opinion seems to be inconsistent with the verses in the Megilah which relate that Esther went "on the third day" to invite the king to her first banquet. The earliest day to which "the third day" may refer is the third day from Haman's decree, or the afternoon of the fifteenth of Nisan. The king's sleep was disturbed on the following evening, and thus it could not have been disturbed before the eve of the sixteenth of Nisan! (The MAHARSHA (15a, DH va'Ya'avor) is bothered by this question and offers a forced solution.)
Perhaps the intention of the Targum is as follows. The Jews who lived outside of Eretz Yisrael never knew for certain which day the Beis Din in Eretz Yisrael had declared as Rosh Chodesh, the first day of the new month. For this reason, they observed two days of Yom Tov. Mordechai thought that Adar of that year had only 29 days, as it has in most years, and thus he wrote that Haman's decree was enacted on the thirteenth of Nisan. He taught his students the laws of the Korban ha'Omer (and the king's slumber was disturbed) on the night which he thought was the sixteenth of Nisan, which was the day on which Haman was hanged. The Targum, however, maintains that Mordechai's reckoning of the chronology was inaccurate; Adar actually had 30 days that year, and the night on which he taught the laws of the Korban ha'Omer (and the king's slumber was disturbed) was actually the fifteenth of Nisan! The dates recorded in the Megilah are based on what Mordechai thought they were and not on the actual dates according to the declaration of the Beis Din in Eretz Yisrael. In fact, Mordechai may never have found out what day the month was declared to be in Eretz Yisrael that year. Accordingly, the Targum may be in agreement with the Gemara and the Midrash. (M. Kornfeld)
3) AGADAH: TWO HOURS INTO THE NIGHT
QUESTION: The Midrash relates that Haman came to Mordechai on the night on which he built the gallows intended for Mordechai. He found Mordechai seated with 22,000 children before him, dressed in sackcloth and studying Torah. The children had been fasting for three days. Haman ordered them shackled in iron chains and appointed guards to watch them. He declared, "Tomorrow I will kill these children first and then hang Mordechai!" All of the children burst out in tears. The Midrash says that even though their parents brought them food with which to break their three-day fast, they refused to eat and continued to fast for another night. Two hours into the night, Hash-m hearkened unto their cries, and "at that moment, Hash-m took the decrees [that He had written to punish the Jews] and tore them up" (Esther Rabah 9:4).
The Midrash says that Hash-m decided to save the Jewish people two hours into the night. What is the significance of these two hours? Why did the salvation of the Jewish people occur two hours into the night?
ANSWER: HA'GA'ON RAV MOSHE SHAPIRO shlit'a answers this question based on a statement made in the name of the VILNA GA'ON (as cited in YEINAH SHEL TORAH). When Esther told Mordechai to have everyone fast for three days, she said, "Also I and my maidens shall fast as such" -- "Gam Ani v'Na'arosai Atzum Ken." She added, "With that (uv'*Chen*)" -- with the merit of the fast -- "I will come to the king" (Esther 4:16).
The Gematriya of "v'Chen" is 72. Esther meant that in the merit of the three-day (72-hour) fast, she would come to the king. (The Midrash (Esther Rabah 9:2) explains that Hash-m never ignores the pleas of the Jews when they are afflicted for three days.) However, when she said that she, too, would fast, she said "Gam Ani... Atzum Ken" -- "Also I... will fast as such." The Gematriya of "Ken" is 70. Esther meant that she would fast for only 70 hours, or two full days and most, but not all, of the third day.
The reason why Esther did not intend to complete her fast on the third day was because she intended to go to the king and invite him to her banquet as part of her efforts to save the Jewish people. Her audience with the king would occur before nightfall on the third day, but she could not stand before the king after having fasted for three full days, weak, disheveled, and with malodorous breath. Therefore, she needed to break her fast two hours early in order to prepare to stand before the king. (The Targum Sheni 6:1, in contrast, writes that part of the miracle was that she was disheveled as a result of her fast when she entered the king's chambers.)
The two hours that were missing from Esther's fast were compensated for by the two extra hours that the children fasted into the night. Their prayers were answered exactly two hours into the night, because at that moment Esther's three-day fast was completed!
(This explanation is consistent with the view of the Midrash which says that Esther appeared before the king to invite him to her banquet on the last day of the three-day fast; see previous Insight.)

OTHER D.A.F. RESOURCES
ON THIS DAF