Misconception: Of the two Megillah readings on Purim, the one at night is the more important one. Therefore, one should be careful to attend the nighttime reading even if he or she will thereby miss the morning reading.
Fact: Halachically, the morning reading is more important than the night reading.
Background: The Shulchan Aruch (OC 687:1; 689:1) rules that on Purim, men and women1 are obligated to hear Megillat Esther twice—once at night and once during the day. This is based on Rabbi Yehoshua ben Levi’s statement (Megillah 4a): “Megillat Esther must be read at night and repeated during the day.” The Talmud cites two verses that allude to the obligation to have two readings (Psalms 22:3; 30:13).2 Tosafot (Megillah 4a, s.v. “chayav adam”) offers three indications3 for the primacy of the morning reading: 1) the language of the first-cited verse (Psalms 22:3);4 2) the main mitzvah of pirsumei nissa (publicizing the miracle) is during the day and 3) consistency with the other mitzvot of Purim, such as seudah (holiday meal), mishloach manot and matanot l’evyonim, all of which can only be fulfilled during the day. The Aruch Hashulchan (OC 687:2) notes that in addition to Tosafot, the Rosh and Ran explicitly state that the daytime reading is more important. The Aruch Hashulchan (687:3) states that the Rambam agrees that the daytime reading is the more important one, despite his ruling not to recite Shehecheyanu over the daytime Megillah reading. Rokeach (Hilchot Berachot 363, p. 254), however, opines that the nighttime reading is primary.
The Noda B’Yehudah (Kamma, OC 41, cited by Sha’arei Teshuvah, OC 687) suggests that the nighttime reading of the Megillah is rabbinic in nature while the daytime reading is based on divrei kabbalah, a prophetic tradition, which in some ways is treated as Biblical law (see Rosh Hashanah 19a). The Pnei Yehoshua (Megillah 4a, s.v. “chayav”) explains that the main reading takes place during the day because that is when the miracle of the Jewish victory occurred (battles are not fought at night). He categorizes the nighttime reading as a “mitzvah b’alma”—a “mere” mitzvah.5 The Peri Megadim suggests that the original enactment by Mordechai and Esther was to read the Megillah during the day only, and the requirement to read it at night was instituted at a later date (Aishel Avraham 692:2).
When the mishnah (Megillah 2:5-6) lists mitzvot that apply during the day and those that apply at night, it lists the reading of the Megillah on the daytime list only. The Binyan Shlomo (58) sees this as evidence that in the Mishnaic period, there was no nighttime reading of the Megillah. He posits that the nighttime reading is a rabbinic enactment of the Amora Rabbi Yehoshua ben Levi. If this is indeed the case, for the first 600 years of Purim celebrations, there was no nighttime reading of the Megillah! Rabbi Tzvi Pesach Frank (Har Tzvi 2:120) rejects Binyan Shlomo’s position.
The Ran (Megillah, p. 1 in Rif pages) draws upon the difference in obligation between the nighttime and daytime readings of the Megillah to posit a surprisingly lenient position. The first mishnah in Megillah offers village dwellers the option of reading the Megillah on the 11th, 12th or 13th of Adar, whichever fell on the Monday or Thursday preceding Purim, when the villagers went into the city for market day. (The villagers relied on the more educated city dwellers to read the Megillah for them.) The Ran notes that this arrangement only provides for the day reading; how did the villagers read the Megillah at night? He suggests that possibly, as part of the special leniency granted to them, villagers were absolved from the obligation to read the Megillah at night.
Assuming the daytime reading is more important, should one who will only be able to hear one of the two readings try to hear the daytime one? The Aruch Hashulchan (OC 687:3) reasons that one should not pass over a mitzvah; therefore, when the opportunity to hear the Megillah reading at night presents itself, one is not permitted to neglect it.
Three berachot are recited prior to the nighttime Megillah reading: Al mikrah megillah, She’asah nissim and Shehecheyanu. In the daytime, it makes sense to recite the first two blessings again, but why repeat Shehecheyanu? Some say that due to the significance of the daytime reading, Ashkenazim6 repeat the Shehecheyanu blessing in the morning.7 Sephardim follow the Rambam,8 who rules that Shehecheyanu is not repeated. Magen Avraham (692:1) advises that when reciting Shehecheyanu for the morning reading, one should have in mind the other daytime mitzvot, such as mishloach manot.
Rabbi Yosef Dov Soloveitchik suggests a novel reason for reciting the daytime Shehecheyanu (Mesorah 18 [Tishrei 5762]: 57-59). The Talmud (Megillah 14a), followed by the Rambam (Hilchot Chanukah 3:10), explains that Hallel is not recited on Purim because the Megillah reading takes its place. Since Hallel can only be recited during the day (Megillah 20b), the Shehecheyanu recited at the daytime reading applies to the Hallel-like aspect of the Megillah.
Taking this to its logical conclusion, the Meiri (Megillah 14) rules that if one does not have a Megillah, he should recite Hallel instead. Rav Soloveitchik disagrees and advises against reciting Hallel. Rabbi Ovadiah Yosef (cited along with many other sources in Yalkut Yosef 5  p. 303) rules that in such a case, Hallel should be recited but without a berachah. In a fascinating corollary, the Peri Megadim (OC, Aishel Avraham 693:2) reasons that on Shabbat of Purim Meshulash, when the Megillah is not read, Hallel should be recited. (Purim Meshulash is a three-day Purim experience celebrated in Yerushalayim when the fifteenth of Adar [Shushan Purim] falls out on Shabbat.) After a lengthy discussion, Dayan Yitzchak Weiss (Minchat Yitzchak 8:64) concludes against reciting Hallel on Shabbat of Purim Meshulash. Rabbi Sraya Duvlitsky (Purim Meshulash, p. 102-3, unnumbered addendum at end) discusses whether someone who did not hear Megillah on Friday of Purim Meshulash should say Hallel on Shabbat. He concludes that he should say it, but without a berachah.
When Purim, Sukkot or Rosh Hashanah falls on Shabbat, the mitzvah of the holiday (Megillah, lulav or shofar) is cancelled by rabbinic decree. According to the Talmud, this is because everyone wanted to do these mitzvot but they didn’t necessarily know how. The rabbis were afraid that someone might inadvertently carry a Megillah, shofar or lulav to the rabbi’s house Friday night to learn how to properly perform the mitzvah and thus violate the prohibition of carrying on Shabbat.
Why did the rabbis not cancel the mitzvah of matzah when Pesach falls out on Shabbat? Rabbi Tzvi Pesach Frank (Mikraei Kodesh, vol. 2  p. 50) suggests that it is because lulav and shofar are mitzvot performed during the day, giving an individual time to receive instruction at night.9 But since the mitzvah of matzah takes place at night, there is no time to receive such instruction! Megillah, however, also takes place at night. Why then is the mitzvah of Megillah cancelled when Purim Meshulash occurs? Rabbi Frank answers that the Megillah reading is cancelled because the nighttime reading is of lesser significance, as the divrei kabbalah requirement applies in the day only.
Rav Soloveitchik (Hararei Kedem, Vol. 1, p. 334-335), based on the Netziv (introduction to Ha’emek Davar, ot bet), offers a fascinating explanation for the two Megillah readings. He explains that the “real” holiday of Purim doesn’t start until the daytime. Hence, Rabbi Yehoshua ben Levi’s directive is not that one must read the Megillah during the night and in the day; rather, one must “read the Megillah and then repeat it.” The night reading is merely “preparation” for the daytime reading. Chazal instituted that the Megillah be read at night so that during the daytime reading people will pay more attention because they have already had the preparatory reading the night before.10
1. In some communities there is an erroneous practice of women not hearing the morning reading of the Megillah. Rabbi Yosef Messas (Mayim Chaim, p. 211) was troubled by this and offered two weak justifications for this custom. (I thank Rabbi Aryeh Frimer for this source.)
2. The first verse relates to day and night as two separate components, while the second implies that the two readings are actually one long continuous mitzvah. Indeed, Rav Soloveitchik understands the Rambam as saying that the two Megillah readings are one long mitzvah (Hararei Kedem, vol. 1 , p. 330). If that is so, questions might arise regarding a person who missed the nighttime reading, similar to the questions raised about one who misses a day in counting the Omer.
3. See also the Rosh (Megillah, ch. 1, 6) for additional reasons.
4. It is possible to misinterpret the Talmudic language that is found almost verbatim in Sofrim 14:18 and SA, OC 687:1, to imply the opposite. The use of the word “repeated” might be seen as implying that it is merely a repeat, a less significant performance of the mitzvah performed the previous night.
5. Former Chief Rabbi of Israel Rabbi Mordechai Eliyahu, following a minority opinion, opined that the nighttime reading is also “divrei kabbalah” (see Rabbi Moshe Harari, Mikraei Kodesh: Hilchot Purim, 3rd ed., p. 73).
6. Rema, OC 692:1. See Chayei Adam 155:24 and the long note there. Note that the Breuer community does not recite this berachah during the daytime reading. Similarly, it does not recite it when blowing the shofar on the second day of Rosh Hashanah.
7. The Pnei Yehoshua (Megillah 4a, s.v. “chayav”) posits that the Shehecheyanu recited before the Megillah reading at night is for the holiday itself, while the Shehecheyanu said before the daytime reading is for the reading of the Megillah. The Meiri (Megillah ch. 1, s.v. “chayav”) says that Shehecheyanu is not recited for the holiday of Purim itself. The MA (692:2) and Rabbi Ovadiah Yosef agree and rule that if one does not have a Megillah, he does not recite Shehecheyanu because the berachah was instituted over the Megillah reading, not over the holiday. (Yabia Omer 6; OC 42:2; cited with many sources in Yalkut Yosef 5  p. 303.) Rabbi Yaakov Emden (Siddur of Rabbi Yaakov Emden, Birchat Hamegillah 5) says that if one does not have a Megillah, he should recite Shehecheyanu over wine at the seudah. The Mishnah Berurah (692:1 and Biur Halachah there) is undecided about the issue.
8. Shulchan Aruch, OC 692:1, based on Hilchot Megillah 1:3.
9. For other solutions, see Ma’adanei Asher—Inyanei Chag HaPesach (5772), 103-104, where he cites, among others, Shu”t Shoel U’mashiv Mahadura 4, 1:5; the Netziv, Haemek She’eilah, She’ilta 67:21; and Pnei Yehoshua, end of Sukkah.
10. Based on this reasoning, one could suggest that one who missed the nighttime reading should read the Megillah twice during the day, not as a make-up reading but because a prior reading is necessary in order to have the required in-depth reading of the Megillah. The idea that the second reading should result in greater understanding of the Megillah is possibly alluded to in the statement by Rabbi Yehoshua ben Levi. In stating that the Megillah should be repeated, he uses a word that can also mean “studied,” perhaps indicating that it should be listened to during the morning reading with greater focus.
The Birchei Yosef (OC 687) quotes those who say that if one missed the nighttime reading, he should read the Megillah twice during the day as tashlumin, a makeup. He disagrees, asserting that tashlumin does not apply to Megillah reading, and thus there is no need for two daytime readings.
Rabbi Dr. Ari Zivotofsky is on the faculty of the Brain Science Program at Bar-Ilan University in Israel.