Parashas Hachodesh marks the beginning of the Pesach season, when we celebrate our redemption from Egypt. The Shabbos reading contains the first mitzvah that was given nationally to the Jewish People—the mitzvah of the New Month.
The first preparation for the nationhood of the Children of Israel relates to the concept of time. In general, everything we do takes place within a specific time framework. Even before we were nationally born out of Egypt, Hashem gave us our own national time framework—defined by the first mitzvah of Kiddush Hachodesh.
In the present article we will discuss a particular facet of time, which is especially relevant for Pesach: the time of chatzos—midnight and midday. Our coming out of Egypt is considered to have taken place at chatzos, at the time of the demise of the firstborns. The time of chatzos-midnight is pertinent in a halachic sense to us on Pesach night, and chatzos-midday for Pesach Eve. On Pesach night, according to one opinion, one needed to finish eating the korban Pesach by chatsos, and on Pesach Eve in the day, according to the Torah, one must remove all chometz by chatsos. (The rabbonon made it earlier.)
Chatzos Yom: Midday
Chatzos means both midnight and midday. Of the two, it is important to begin with midday, which seems relatively easy to calculate. The time of chatzos hayom, midday, is simply the time when the sun is in the middle of its journey across the sky, on a straight line above one’s head (see Tosafos Yom Tov, Pesachim 5:1).
According to most authorities, this time is easily calculated by finding the midpoint between the time of sunrise (zerichah) and the time of sunset (shekiyah)—it is simply the midpoint of the sun’s journey across the sky. Based on this understanding, the time of midday changes from day to day, depending on the times of sunrise and sunset. (This is stated in Shaarei Teshuvah, Orach Chaim 89:1).
Although this is the opinion of most authorities, it is noteworthy that Rav Moshe Feinstein (Iggros Moshe, Orach Chaim 1:24; 2: 20) had an original approach to the time of chatzos, arguing that halachic midday occurs at a fixed time throughout the year. Rav Moshe even notes that he received this understanding of chatzos from his father, and he proves the point from Rashi (though the proof is somewhat difficult to understand). This principle is also stated by the Aruch Ha-Shulchan (Orach Chaim 233:14), who likewise writes that the time of midday is always the same.
However, the great majority of authorities endorse the simple ruling that calculates chatzos as the time at which the sun is the above our heads. This is the customary ruling which is cited by virtually all calendars.
Halachic Significance of Midday
The time of chatzos hayom is of great importance for many halachic purposes. The first, which is a Torah law, is concerning the prohibition of chametz, which begins at chatzos on Pesach Eve. From this time and onward, it is forbidden to have chametz in our possession.
The Gemara (Pesachim 4b) derives this halacha from the Torah obligation to destroy chametz from our possession “on the first day.” This cannot apply to destroying chametz on Pesach itself, since we are forbidden to have any chametz in our possession on Pesach (and destroying it implies that it is in our possession), and therefore it must refer to the eve of Pesach, from midday (when the time for bringing the Pesach offering theoretically begins).
According to most Rishonim, the same is true of the Torah prohibition against eating chametz. Just as the prohibition against keeping chametz in our possession applies from chatzos, so too does the prohibition against eating chametz (this is the ruling of the Rambam, as well as the Shulchan Aruch, Orach Chaim 443:1 though some write that the Torah prohibition against eating chametz only begins at night).
In addition to the Torah prohibition against chametz, there are a number of common rabbinic halachos for which chatzos is the relevant halachic time. For instance, the prohibition against taking a haircut, entering a bathhouse, and eating a festive meal before davening Minchah, begins every day at chatzos. Likewise, the Shacharis prayer can be said up to chatzos, if the proper time was inadvertently missed. Furthermore, it is prohibited to fast up to chatzos on Shabbos and festival days (Magen Avraham 157:6), and the prohibition against sitting on a regular chair on Tisha Be’Av ends at chatzos.
Also, the beginning of the time for davening Minchah is half-an-hour after chatzos, a halacha derived from the Torah time for bringing the afternoon Tamid offering.
Chatzos Laila: Midnight
Determining the time of midnight is more difficult than the time for midday: by contrast with the day, there is no astronomical indication of its arrival.
According to almost authorities, midnight is defined as corresponding to midday: midday is the middle of the day, and midnight the middle of the night. According to some authorities it is the halfway point between nightfall (tzeis) and daybreak (alos). This ruling is elucidated by the Tashbatz (Vol. 1, no. 109), the Shulchan Aruch Harav (1:8), and by many other Poskim (see Kaf Hachaim1:8). This opinion is ruled by the Magen Avraham (1:4, citing Shut Shev Yaakov Vol. 1, no. 1).
Based on this calculation, there is no necessary correlation between the halachic times of midnight and midday. The time of midnight is the midpoint between the beginning of the night (nightfall, tzeis hakochavim) and the start of the day (daybreak, alos hashachar)—a time that has no connection with the halfway point between sunrise (hanetz hachama) and sunset (shekias hachama).
However, most Poskim write that the time of midnight can be calculated by adding twelve hours to the time of midday: the time of midnight is linked to the time of midday. This equivalence is stated by Shut Shev Yaakov, by the Yad Efraim (1), the Ya’aros Devash (Vol. 1, Derush15; Vol. 2, Derush 12), the Siddur Ya’avatz, and others and is ruled by the Mishna Beruro (1, 9).
According to this approach, the time of midnight is the midpoint between sunset and sunrise—just as midday is the midpoint between sunrise and sunset. The logic of this is that midnight is the astronomical parallel of midday: If at midday the sun is above our heads, at midnight the sun is as it were beneath our legs—the midpoint of the path of the sun below the earth.
Yet, there are authorities who note that this method of equivalence should not be used for determining the time of midnight, because this is not the actual middle of the night. Rather, the time should be calculated, by finding the halfway point between nightfall and daybreak. If we apply the nightfall of the Geonim (as ruled by the Vilna Gaon and the Ba’al Hatanya, which is only a few minutes after sunset), this calculation will yield a far earlier time for midnight than the equivalent of midday.
Thus, in his approbation to the sefer Matzos Mitzvah, the author of Pe’as Hashulchan criticizes the custom of relying on the time of midday also for midnight, writing that one should be stringent (for Torah matters, such as eating matzah) in following the earlier time as calculated above. The Eshel Avraham (Butshatch, 477) is doubtful over which is the true time for midnight: the equivalent of midday, or the midpoint between nightfall and daybreak.
The most important halacha of midnight is the eating of matzah today, and in times of the Mikdash the Pesach offering, before chatzos. Rabbinically, however, some mitzvos including the recital of kriyas shema (Berachos 2A) that can be performed by Torah law until sunrise should be performed before chatzos.
The Propitious Time of Chatzos
The Magen Avraham (1, 4) cites the Zohar (Vayakhel) that for saying Tikun Chatsos the period of the night should always we considered as a twelve-hour (regular hours) period, in summer and in winter. Th Machatzis Hashekel brings an opinion that this means one should count a period of twelve hours from the time of nightfall (when stars come out). Midnight is six hours after nightfall. Note that according to this definition, a summer night in many parts of the world can continue well into the morning hours of daylight.
The Magen Avraham (233:4) notes for other halachos (e.g. when one must say kriyas shema, eat matzo etc.) the Zohar does not apply. The rationale is that concerning the propitious time of chatzos, which is the appropriate time for tikkun chatzos, we do not consider the astronomical cycles of the day and the night—which do not exist concerning Hashem—but rather establish the time of chatzos based on a twelve-hour count of the night. However, concerning prayer, which corresponds to the sacrificial service and depends on earthly calculations, we base our times on nightfall and daybreak. This likewise applies to times for Shabbos and festivals.
It emerges according to the Magen Avraham that there are two distinct times for midnight: one is the time of midnight for purposes of regular halachah, and another is the time of midnight as a propitious time, which is the appropriate time for Tikkun Chatzos. The time of midnight is indeed a propitious time, as Chazal point out (see Yevamos 72a, and Rashi) concerning Torah and prayer, and this is the reason why some are particular to awaken from their sleep at midnight—as King David used to do (Berachos 3b)—for prayer and Torah study (see Tur, Orach Chaim 1).
In fact, some go so far as to suggest that concerning the virtue of midnight, the correct time does not vary from place to place, but follows midnight of the Land of Israel. This principle is mentioned by the Chasam Sofer (Toras Moshe, Bo), and noted by the Mor U-Ketziah (Orach Chaim 1). Moreover, Rav Yaakov Emden (344) applies the same idea to the changeover of days: the principle determination of which day of the week it is at any given time depends on the Land of Israel.
Other authorities, however, do not make any mention of the importance of the Land of Israel in this regard, and Shut Iggros Moshe explicitly rules out this suggestion, explaining that chatzos is calculated for each place according to its local times.
The principle halacha is that the times of midday and midnight change from day to day. According to the Iggros Moshe they are at a fixed time of the day (midday on the day of the equinox).
Based on the standard method of calculation, midday (chatzos hayom) is the time when the sun is above our heads, which is the halfway point between sunrise and sunset. The general custom is to use the same time for midnight, and this is the time that generally appears in calendars.
Some are stringent for purposes of Torah law (eating matzah on Pesach, but not for afikoman) to use an earlier time of midnight, which is the midpoint between nightfall (the time of tzeis hakochavim) and daybreak.