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Sanhedrin, 42


QUESTIONS: The Gemara (41b) teaches that Birkas ha'Levanah (or "Kidush ha'Levanah") may be recited until the moon no longer appears diminished. Rav Yehudah says that this refers to the seventh day of the month, while Neherda'i say that this refers to the sixteenth day of the month. The Poskim rule like Neherda'i (SHULCHAN ARUCH OC 426:3). The Poskim explain, based on the TESHUVOS MAHARIL (#19), that when the Gemara says "until the sixteenth," the sixteenth day is *not* included, and Birkas ha'Levanah may be said only until the fifteenth day of the month. In reality, though, even the fifteenth day is too late to recite Birkas ha'Levanah; rather, the latest time for reciting Birkas ha'Levanah is when half of the length of the month has passed since the time of the Molad (this is 14 days, 18 hours, and 396 1/2 Chalakim, as the length of the month is 29 days, 12 hours, and 793 Chalakim (out of 1080 Chalakim in one hour)). After that time, the moon's appearance begins to diminish again and it is too late to recite Birkas ha'Levanah.

For this reason, the Maharil concludes that in a month when there is a lunar eclipse (and thus the exact moment that the moon's appearance begins to diminish is evident, since the lunar eclipse is caused by the moon's opposition to the sun) one may not say Birkas ha'Levanah after the eclipse, since clearly half of the month has passed.

The time of the Molad is printed in most Halachic calendars and announced at the time that we recite Birkas ha'Chodesh in the synagogue on the Shabbos before Rosh Chodesh. The last moment to recite Birkas ha'Levanah is determined by simply adding half of a month to the moment of the Molad.

However, this calculation is problematic for a number of reasons. First, the midpoint of the month is the point at which the sun and the moon are in astronomical opposition (that is, the earth is directly between the sun and the moon). This occurs at one point in time, regardless of where on the globe a person lives. The moment of the Molad is the point at which the sun and moon are in perfect conjunction (that is, the moon is exactly between the earth and the sun). This also occurs at a single moment in time and does not depend on a person's location on the globe. It is an astronomical phenomenon and is not subjective. The time of the Molad that we announce in synagogue is the moment at which the Molad occurs according to the time in Yerushalayim. However, depending upon a person's location around the world, the time of the Molad -- and the time of opposition half a month later -- will occur either be earlier (for the countries west of Yerushalayim) or later (for the countries east of Yerushalayim) because of the time difference! Why, then, do all Jewish communities use the same time of day for the latest time to recite Birkas ha'Levanah? The latest time should depend on the person's longitude!

Second, the time clock that is used in determining the Molad is not a clock that is used *anywhere* on the globe today. It is measuring the solar time (the time according to the movements of the sun) in the exact longitude of Yerushalayim. Today, the time used in Yerushalayim is known as Cairo time (the solar time as measured by the longitude of Cairo), which is 21 minutes later than the actual solar time in Yerushalayim (for example, when the actual solar time in Yerushalayim is 1:00, the time that appears on the clocks is 1:21 (Cairo time)). Based on this, if we want to know the true time of the Molad, the time of opposition according to our clocks, then in Yerushalayim we should subtract 21 minutes from the time that is announced in the synagogue, and in other places around the globe we should subtract a number of hours and minutes depending on the exact solar time of that particular longitude.

Third, the length of the month on which we base our calculations -- 29 days, 12 hours, and 793 Chalakim -- is not the actual length of every lunar cycle. Rather, it is the average length of a month. The month itself might be either longer or shorter (by up to 14 hours, depending on the path of the ellipse, the varying orbit of the moon around the earth), as the Gemara says in Rosh Hashanah (25a). The reason for this is because while the moon is circling the earth, the earth is also moving further along its path, so that the moon will not reach conjunction until it travels a little more than a full orbit around the earth in order to catch up with the forward movement of the earth. Since the moon's orbit is elliptical and it travels slower at the point of aphelion (the point of the orbit of the moon around the earth at which the moon is farthest from the earth), it will travel that extra part of the ellipse and catch up with the earth either faster or slower, depending on whether it is closer to aphelion or close to perihelion as it reaches the point of conjunction. Accordingly, adding half of a month (14 days, 18 hours, 396 1/2 Chalakim) to the time of the Molad will not accurately determine the time at which the moon actually begins to diminish!

The same questions may be asked about the time of the Molad that is announced in the synagogue. Why do we not announce the actual time of conjunction as the time of the Molad? The TIFERES YISRAEL (in Shevili d'Raki'a, beginning of Seder Mo'ed) addresses this question. He answers that since, in the times of the Beis ha'Mikdash, the Sanhedrin proclaimed the new month in Yerushalayim, today we, too, mention the time of the Molad according to the time in Yerushalayim. This answer is appropriate with regard to the announcement that we make for the Molad in the synagogue, which is not for the sake of any Halachic purpose, but rather is "Zecher la'Mikdash." However, the calculation of the time of opposition with regard to the latest time at which one may say Birkas ha'Levanah -- which depends on the actual time of opposition, as the Maharil writes -- should be based on the actual astronomical time of opposition!


(a) The ALAH YONAH (Rav Yonah Mertzbach) explains that we find that the Chachamim simplified mathematical calculations which are required for Halachos which affect the community at large. For this reason, we find that a different calculation for the length of a year is used when determining when to begin saying "v'Sen Tal u'Matar" in the Shemoneh Esreh, or when to recite "Birkas ha'Chamah," than that which is used for calculating which year should be a leap year. For the former Halachos, the Chachamim used the simple equation of Shmuel (Eruvin 56a; see Insights there), according to which the year is exactly 365 days long, and for the latter Halachah the Chachamim used the calculation of Rav Ada. The same might apply with regard to calculating the length of the month: when determining the latest time to say Birkas ha'Levanah, the Chachamim simplified the calculation and said simply to add a set amount of time to the time of the Molad which is announced at the beginning of the month. Nevertheless, the Maharil writes that after an eclipse, one may not recite Birkas ha'Levanah, because the eclipse at is an obvious sign that clearly shows that half of the month has passed, and it is easy to act in accordance with that sign.

(b) The TESHUVOS BENEI TZION (1:42:10; Rav David Spira, Yerushalayim 1938) explains that the Chachamim did not require that we calculate the true Molad (as opposed to the average Molad) when determining the latest time to say Birkas ha'Levanah, because they relied on the principle of "Rov," following the majority. That is, since the time that we announce for the Molad can be either before, on, or after the occurrence of the true Molad, there is a greater chance that it will be *after* or *on* the Molad than *before* the Molad. We rely on this Rov to allow Birkas ha'Levanah to be recited until half a month has passed from the average time of Molad that is announced in the synagogue on the Shabbos before Rosh Chodesh.

(Even though we usually do not rely on the principle of Rov to determine something which can be precisely verified, nevertheless we rely on Rov in this matter because the verification of the time of the Molad is so complicated, even for experts. The exact Molad is therefore considered somewhat "inaccessible" without relying on Rov.)

Why, though, is it permitted for Jews in all longitudes to rely on the announced time of the Molad for calculating the latest time to say Birkas ha'Levanah, without taking into account the different time zones?

The Benei Tzion points out that this question is relevant primarily to people west of Yerushalayim. If they wait until the last hour to say Birkas ha'Levanah, then people to the west of Yerushalayim will say Birkas ha'Levanah *after* the true time limit has passed (since they are looking at their clocks and not at the Yerushalayim clocks). Those to the east of Yerushalayim will *stop* saying Birkas ha'Levanah *earlier* than they really have to, which is justifiable. According to a well-known Halachic ruling (based on the BA'AL HA'ME'OR to Rosh Hashanah 20b; see Insights there, and see KUZARI 2:20), the "western limit" of the globe is 18 hours west of Yerushalayim. Our question may therefore be rephrased as follows: Why do we allow those living to the west of Yerushalayim to say Birkas ha'Levanah 18 hours after the time has passed?

This question, the Benei Tzion asserts, may be answered based on a remarkable ruling of the TESHUVOS CHASAM SOFER (Orach Chaim 102). The Chasam Sofer permits Birkas ha'Levanah to be said on the sixteenth day of the month (in contrast to the MAHARIL and BEIS YOSEF OC 426) in a time of need. He explains that when the Gemara says that Birkas ha'Levanah may be recited until the sixteenth, it means *up to and including* the sixteenth. Even though the moon is already full after 14 days and 18 hours (see above), it remains full for another day and a half. The Chasam Sofer explains that even though the moon begins to diminish when half of the month has passed, nevertheless it is not obvious to the eye that the moon has begun to diminish until after the sixteenth. (When the YAD RAMAH to Sanhedrin was printed it was discovered that he says on this point exactly what the Chasam Sofer says.)

The Chasam Sofer suggests a proof for this from the Gemara in Rosh Hashanah (20b) which says that the new moon is not visible until 18 hours after the Molad. Just as its growth is not visible for 18 hours, its diminution is not apparent until 18 hours half passed after the midpoint of the month.

The Benei Tzion explains that according to the Chasam Sofer there is an 18 hour leeway for reciting Birkas ha'Levanah after the full moon appears (i.e. after the point of opposition). Because of this, the Chachamim allowed the people who live until the western limit of the world -- which is 18 hours to the west of Yerushalayim -- to continue saying Birkas ha'Levanah until the latest time as it appears on *their* clocks even though they will be saying Birkas ha'Levanah up to 18 hours after the actual time of opposition.

(Many authorities have pointed out that the Chasam Sofer's argument is weak. The reason it takes 18 hours to see the new moon after the Molad is because it is too close to the sun and the light of the sun hides it. The full moon, the moon in opposition, on the other hand, is on the opposite side of the sky from the sun and thus the light of the sun does not impede its appearance. Nevertheless, the assertion that the appearance of the diminution of the full moon is delayed for some time is supported by the Yad Ramah.)

The Benei Tzion does not explain why we do not take into account the 21-minute difference between the clock used in Yerushalayim and the actual solar time in Yerushalayim (or, in other words, the difference between the time zone of Cairo and the actual solar time in Yerushalayim). That is, the true Yerushalayim time is 21 minutes *later* than what the clocks actually read in Yerushalayim (i.e. Cairo time). Hence, the latest time for Birkas ha'Levanah will arrive 21 minutes *before* our clocks read that time, and thus if we wait until our clocks reach the latest time, we have actually *passed* that time already! (For example, if the latest time, based on the calculation of the Molad and as expressed in the Halachic calendars, is 1:21 AM, then when our clocks in Yerushalayim reach 1:00 AM, we may no longer say Birkas ha'Levanah, since the real Yerushalayim time of 1:21 has already arrived.)

HALACHAH: According to what we have written above, there are several practical implications with regard to the latest time to recite Birkas ha'Levanah.

(a) The MISHNAH BERURAH (OC 426) writes that l'Chatchilah one should not say Birkas ha'Levanah after half a month has passed from the time of the Molad. B'Di'eved, if half of the month (14 days, 18 hours, 396 1/2 Chalakim) has passed but fifteen full days have not passed, then one may still say Birkas ha'Levanah (as the Shulchan Aruch rules). However, on the sixteenth day one should say it without "Shem u'Malchus," the Name of Hashem in the blessing (because the view of the Yad Ramah is a minority opinion).

(b) After an eclipse, one should not say Birkas ha'Levanah, since it is obvious that the moon's appearance has begun to diminish. Some say that even though the point of opposition is the midpoint of the eclipse, one should not say Birkas ha'Levanah from the time that the umbra, the shadow of the earth, covers the entire moon. Even though the moon is still visible (but darker), one should no longer recite Birkas ha'Levanah even before the midpoint of the eclipse arrives, since the moon has begun to diminish in brightness (because of the eclipse). (BIRUR HALACHAH of Rav Yechiel Avraham Zilber.)

Another point to take into consideration is that contrary to what we assumed earlier, the point of opposition might *not* be the same for all places on the globe. The reason for this is because there are two ways to determine the point of opposition. First, opposition can be the point at which the sun and moon are on opposite sides of the earth to an objective observer looking down from above the orbit of the earth. Second, opposition can be a subjective point at which the moon is at the opposite side of the earth from the vantage point of the observer on the dark (night) side of the earth. According to this second approach (which the TIFERES YISRAEL in Shevili d'Raki'a seems to adopt with regard to measuring the time of the true Molad), people further to the west might see the moon at opposition from their vantage point, for example, at the *beginning* of the night, while people further east will not see the moon catch up to the point of opposition from their vantage point until two or three hours later.

If this is the way to measure opposition, then people further east might be able to say Birkas ha'Levanah even after the eclipse, since the moon has not yet reached opposition from their vantage point (even though the objective point of opposition -- i.e. the midpoint of the eclipse -- has passed).

According to the way the Benei Tzion explains, if exact tables of opposition are available, then it would be best to recite the Birkas ha'Levanah *before* [18 hours have passed after (according to the Chasam Sofer)] the point of actual opposition. In Europe and Asia this is not relevant, since the actual opposition can only be up to 14 hours earlier than the average opposition (which is included in the 18 hour leeway period). However, this would be relevant in North and South America.

Rav Alexander Shutz (Kiryat Sefer, author of KUNTRUS DI'SHEMAYA) points out that even when there is no eclipse, it should easily be discernible when the moon has passed opposition: by seeing whether the sun has set before the time that the moon rises. (That is, if the moon is not in the sky at the time that the sun sets, then it is after opposition.) We have learned that if it is obvious that opposition has passed, then one should not say Birkas ha'Levanah, as the Maharil explains, and therefore perhaps even in Yerushalayim we should not give an extra 18 hours for Birkas ha'Levanah, since there is an obvious sign that the moon has passed opposition. To this end, Rav Shutz prepared tables of the times of true opposition (see Chart).

All of these arguments and calculations pertain only to the latest time to say Birkas ha'Levanah. However, there is no need to change the announced time of the Molad when the time is announced in the synagogue for Birkas ha'Chodesh. This is because, as we have explained, it has become the accepted practice to announce the time of the Molad from the vantage point of Yerushalayim as "Zecher la'Mikdash," regardless of where a person is, even though that time will not be consistent with any clocks in the world (since it is true Yerushalayim time). For this reason, the Poskim point out that there is no point in adding an hour to the time of the Molad printed in the Halachic calendar when "Daylight Savings Time" is in use either locally or in Yerushalayim, since the time of the Molad is on an imaginary clock and is not based on an actual clock, such as Cairo time or Greenwich mean time.

AGADAH: The Gemara teaches the text of the blessing of "Birkas ha'Levanah." Included in the blessing are the words, "... Ateres Tiferes la'Amusei Vaten..." -- "To the moon He said that it should renew itself as a crown of glory for those carried by the womb...." RASHI explains that these words allude to the splendor of the Jewish people which, like the moon, will one day be restored to its full glory.

What is the deeper significance behind the comparison of the moon to the splendor of the Jewish people?

(a) We can understand this analogy better based on the Midrash (Shemos Rabah 15; see also RABEINU BACHYE to Bereishis 38:30, cited by SHULCHAN ARUCH OC 426:2) which teaches that just as the moon waxes and wanes over a thirty-day period, so, too, the power of the kingdom of Yisrael "waxed and waned" over a period of thirty generations. It grew for fifteen generations until it was full -- from Avraham Avinu until Shlomo ha'Melech, and then it diminished for fifteen generations, culminating in the reign of Tzidkiyahu ha'Melech, whose eyes were blinded by the enemy at the time of the destruction of the Beis ha'Mikdash (Yirmeyahu 52:11), a sign of the complete loss of the light of the moon. The return of the moon's light after the Molad is a sign that the dynasty of the Malchus of Beis David, too, will return to its former glory.

This concept is also reflected in the Gemara in Rosh Hashanah (25a) which says that Rebbi told Rebbi Chiya that when he sanctifies the new month, he should send Rebbi a message saying, "David Melech Yisrael Chai v'Kayam." Rashi there explains that the Davidic dynasty is compared to the moon (as mentioned in Tehilim 89:37). The MAHARATZ CHIYUS cites proof from the Yerushalmi in Sanhedrin that it was indeed common practice to announce the new month with the phrase, "David Melech Yisrael...." The Chachamim viewed the new moon as a sign of hope for the rebuilding of the Davidic dynasty of Yisrael. This is also the source for the present day custom of mentioning this phrase during Birkas ha'Levanah.

(MENACHEM MESHIV NEFESH in Rosh Hashanah there cites the SHA'AR EFRA'IM (10:36) who adds in the name of the BRIS KEHUNAS OLAM that the Gematriya of "David Melech Yisrael Chai v'Kayam" is 819, the same value as the Gematriya of "Rosh Chodesh" (spelled Malei, with a Vav).)

(b) It is customary, upon completing the recitation of Hallel on Rosh Chodesh, to mention the verse "v'Avraham Zaken Ba ba'Yamim, va'Hashem Berach Es Avraham ba'Kol" -- "And Avraham was old, he had come of days, and Hashem blessed Avraham with everything" (Bereishis 24:1). What is the connection between Rosh Chodesh, or Hallel, and this verse?

The RAMBAN comments on this verse that the word "ba'Kol" is an allusion to Hashem's attribute of Malchus, Kingship. Since Avraham Avinu taught the world that Hashem is the Melech, Hashem blessed Avraham Avinu that he would represent the Malchus Shamayim in this world. Thus, we find that Avraham was accepted by all of the nations as king (see Rashi to Bereishis 14:17). Avraham's kingship was the beginning of Malchei Yisrael, as the Midrash cited above mentions, and the first of the thirty kings whose kingship followed the path of growth and diminution of the moon. Avraham Avinu merited this through teaching the praise of Hashem to the world. Therefore, on Rosh Chodesh -- the day on which we remember Hashem's promise to restore the kingdom of Yisrael to its former glory, and we sing the praises of Hashem -- we allude to Hashem's promise to revive Malchus Yisrael by reciting this verse which alludes to the birth of Malchus Yisrael. (Heard from RAV MOSHE SHAPIRO.)


QUESTION: The Mishnah teaches that Sekilah is administered outside of Beis Din. This is learned from the verse, "Hotzei Es ha'Mekalel El mi'Chutz la'Machaneh" (Vayikra 24:14). The Gemara explains that the Mishnah is teaching that even when the members of Beis Din are not sitting inside of the city, but rather outside of the city, they are still required to leave the courthouse and perform the executions outside of Beis Din. The reasons, explains the Gemara, are so that Beis Din will not look like a place of killers, and so that the guilty party has more time to argue his case while he is being brought to the execution place. When, however, Beis Din is sitting inside of the city, there is another reason why the executions must be performed outside of Beis Din -- because the verse says, "El mi'Chutz la'Machaneh," which teaches that the executions must be performed outside of the city altogether.

The Mishnah seems to be quoting the verse which teaches why Beis Din must perform executions outside of the court. Why, then, does the Gemara need to give logical reasons for why the executions must be performed outside of the court? (TOSFOS DH Ki Heichi)


(a) TOSFOS answers that the Mishnah is giving a reason for why the executions are done *outside* of Beis Din. This is learned from the verse. However, the verse does not teach that the executions must be performed *far* from Beis Din. The Gemara's logical arguments teach that the executions must be done at a considerable distance from Beis Din and not immediately outside of Beis Din. This also seems to be the intention of RASHI on the Mishnah (DH Chutz, DH she'Ne'emar). (See RABEINU YONAH for a different approach.)

(b) The RAMBAM (Hilchos Sanhedrin 12:3) seems to have a different approach to this question. The Rambam writes that the verses teaches that the executions should be done far from Beis Din, but that the verse does not teach *how* far. The Rambam suggests that perhaps the distance should six Mil, or one and a half Parsa'os. He bases this distance on the fact that we find that Moshe Rabeinu's court was located in the center of the encampment of Yisrael, which stretched for a length of three Parsa'os (Sanhedrin 5b). In order to leave the encampment, then, the Beis Din had to walk one and a half Parsa'os, or six Mil. That was the distance of Moshe's court in the center of Machaneh Yisrael to the outskirts of Machaneh Yisrael where the executions were performed.

The Rambam does not differentiate between a Beis Din that is inside of the city or a Beis Din that is outside of the city. Rather, he seems to learn from the verse, which teaches that executions are to be done outside of the three Machanos, that executions are performed at a distance of six Mil from the Beis Din, regardless of where the Beis Din happens to be located. That is, the point of the verse is not to perform the execution outside of the Machaneh, but to perform it at the *distance* which existed from Moshe (i.e. Beis Din) to the edge of the Machaneh.

Support for the Rambam's interpretation can be adduced from a number of sources.

First, the Gemara asks why the Mishnah says that the execution is done outside of court, when it has to be done outside of all three Machanos. The Gemara answers that our Mishnah is teaching that even when the Beis Din "goes out" of the three Machanos, the execution place still must be far away. Why does the Gemara have to say that the Beis Din "goes out" of the three Machanos? It should say if the Beis Din already "is outside" of three Machanos, then it must perform the execution outside of the court! Apparently, the reason the Gemara does not say that Beis Din is already outside of three Machanos is because it is unusual for the Beis Din to be outside of the city limits. However, when the city is not a walled-city, then even when the Beis Din is sitting inside of the city it is considered outside of three Machanos. The requirement to perform executions outside of three Machanos only requires that executions not be performed inside of walled-cities; they *may* be performed inside of a non-walled-city! Since every large city, walled or not walled, has a Beis Din, it should be easy to find a Beis Din that sits outside of three Machanos!

This question may be asked only if we understand the three Machanos to be referring literally to the Machanos that exist at the time of Beis Din. This is indeed the way most Rishonim explain, and for this reason they write that the verse requires executions to be performed outside of walled cities. (See TOSFOS DH Beis ha'Sekilah, RASH and ROSH in Kelim 1:7, RASHI (DH d'Iy Nafik) also mentions a walled-city; see also RABEINU YONAH.) However, the RAMBAM seems to have learned that the verse is simply describing the distance between the Beis Din and the place of execution. We see from the verse that no matter where the Beis Din is sitting, it must distance the execution. That is why the Gemara asks why the Mishnah only requires executing *outside* of Beis Din but not *far* from Beis Din. The Gemara's answer, according to the Rambam, might be that even when the Beis Din follows the guilty party to the place of execution, the execution still should not be performed in the presence of the members of the Beis Din, but away from the members of the Beis Din.

Second, according to the explanation of Tosfos, how does the Gemara know that the execution must be performed *far* from Beis Din when Beis Din is sitting outside of the city, if that is not written in the Mishnah (which says only to perform the execution *outside* of Beis Din)?

Third, the ROSH (Kelim 1:7) asks why the Mishnah does not list the Halachah that executions may not take place in a walled-city in its list of all of the unique aspects of walled cities? According to the Rambam, this is not a Halachah that is limited to walled-cities and thus there is no reason for the Mishnah in Kelim to mention it.

Fourth, the Rambam's explanation might also answer our original question. The Gemara is explaining how the words "mi'Chutz la'Machaneh" means outside of three Machanos, and not simply outside of a walled-city (as it usually means). How do we know that the verse is giving a measure of distance? The Gemara answers that, logically, it would seem more appropriate that the limitation on executions is not related to the Kedushah of the city, but rather it is because the Torah was concerned with the practical considerations of not having the Beis Din look like killers, and giving the guilty person more time to think of a defense. Because of this, we explain that the verse is only teaching a measure of distance, three Machanos, and is not requiring that we execute outside of walled-cities. Through the same logic we may conclude that the verse does not allow the execution to take place in the presence of the members of the Beis Din even if they are no longer in the courthouse.

(According to the Rambam, the reason the defendant is more likely to think of a defense outside of court is because he is too nervous to think clearly while standing in front of the people who incriminated him. Therefore, we walk him a distance from the court so that he can collect his thoughts and think of a defense. If the court would convene at the place of execution, then it would defeat the purpose of executing him outside of Beis Din.)

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