Ibn Ezra on Leviticus 23:4

ואחר כן הזכיר המועדים ואמר בשבת אלה הם מועדי ובמועדים אמר במועדם והטעם באיזה יום שיהיה מהשבוע והנה אני נותן לך כלל בדברי המועדים כי בזמן שבית המקדש קיים היו המועדים נמסרים לבית דין הלא תראה כי אמר על פסח חזקיהו ויועץ המלך ואחר שקבע ראש חודש ניסן עבר השנה ובזה תפשוהו חכמינו ז״ל כי היה ראוי שלא יעבר ניסן בניסן והמעתיקים אמרו כי בית דין היה מסתכל בדברים רבים בקביעות השנה ואמרו על רבי עקיבא שקבע שתי שנים מעוברות שנה אחר שנה לפי צורך השעה ואין בכל המקרא ראיה איך היו ישראל קובעים החדשים והמועדים ומה שאמר הגאון כי על חשבון העיבור היו נסמכים איננו אמת כי במשנה גם בתלמוד ראיות שהיה פסח בבד״ו גם שני מעשיות שם ועבור השנים קרוב מתוספת שנת החמה על הלבנה ואיננו על דרך הקדמונים ותחלת החשבון וי״ד פי׳‎ שים עם לבהר״ד ד״ח תתע״ו יבא המולד וי״ד כי שנה נוספה להחל מחשבון בהר״ד בעבור חמשה הימים שהיו קודם בריאת האדם ויום בשנה חשוב שנה וזה לא יזיק על כן לא תוכל לקחת תוספת שנה נוספה כי לא היתה והנה העבור אחר שנה וחצי שנה והעבור בנוי על המהלך התיכון על כן אמרו פעמים שבא בארוכה ובקצרה ואין הקביעות רודף אחר ראית הלבנה בירושלים או בקצה מזרח או במערב כלל והעד מקום המחברת התיכונה כי הנה היא על ירושלים ועוד שראינו פעמים רבות הלבנה בחדש ניסן בליל שני וכן היתה נראית בכל העולם וקביעות החדש היה ליל שלישי וכן אירע לשלשה חדשים קודם ניסן וזה נתקן בשנת גטר״ד בעבור הדחיה גם פעמים היה הקביעות בתשרי יום חמישי ולא נראית הלבנה בליל שבת והיה האויר זך וזה יקרה בכל שנה שהמולד קרוב מחצי היום והיתה הלבנה בחצי גלגל הגבוה גם אין הקביעות בנוי על עת התחברות המאורות אפילו במהלך האמצעי כי הנה בטור״ד גם גטר״ד יוכיחו ולולי שלא אאריך הייתי מפרש סוד העיבור וסוד ההלכה החמורה שהוא נולד קודם חצות והכלל שחז״ל העתיקו לנו שנסמוך על העיבור בגלות וכן קבלנו מפי נביאים ולא נוכל לעשות דבר אחר טוב ממנו וזה ששמו ב׳‎ ימים בגלות והוא על דבר ספק והמתענים יום הכפורים שני ימים מה יועילם בעבור הדחיות כי בשנת גטר״ד אם על המולד היה ראוי שיתענה בשמונה לקביעתנו וכי למה נעוות אנחנו חשבון שנתנו בעבור שנה אחרת וכן יקרה להם עם הראיה: Scripture then mentions the festivals (v. 4). The Torah says, even these are My appointed seasons, with regard to the Sabbath and in their appointed season with regard to the festivals. The meaning of in their appointed season is, in any day of the week in which they fall. Note, I will now lay down a general rule with regard to the festivals. During the time of the Temple the festivals were in the hands of the Beth Din. Do you not see that Scripture says, For the king had taken counsel (II Chron. 30:2), with regard to the Passover proclaimed by Hezekiah.³Hezekiah put off the observance of Passover for a month. According to I.E., Hezekiah’s actions were based on a ruling of the Bet Din. See Vol. 1, pp. 9,10. After Hezekiah established the new moon of Nisan he proclaimed a leap year.⁴And proclaimed that Passover be observed in the next month. Our sages, of blessed memory, criticized him for this, for he should not have added a Nisan on Nisan.⁵See Berakhot 10b. The transmitters of tradition said that the Beth Din took many things into consideration in estabhshing the year.⁶See Sanhedrin 11a,b. The Bet Din had to consider many things in deciding whether or not to make a year a leap year. They said, regarding Rabbi Akiba, that he established two leap years back to back according to the needs of the hour.⁷San. 12a. However, the text there speaks of three years. Hence Krinsky suggests emending I.E. to read three years. Vat. Ebr. 38 omits the word two. It reads, “He established leap years back to back.” There is no proof in Scripture as to how Israel established the months and the festivals. The Gaon’s statement to the effect that they relied on the intercalational calculation⁸The rules governing the establishment of the fixed Jewish calendar. is not true, for there are proofs in the Mishnah and also in the Talmud that Passover fell on a Monday, Wednesday, and Friday.⁹Which cannot occur under the rules of the fixed Jewish calendar. There are also two stories in the Talmud [which show that they did not rely on a fixed calendar].¹⁰The Mishnah, Rosh Ha-Shanah 2:9 records a controversy between Rabban Gamliel and Rabbi Joshua as to when Yom Kippur fell in a certain year. If the rabbis of the Mishnah had used a fixed calendar there would be no place for this difference of opinion. The Mishnah (Ibid. 2:8) also reports an instance of two sets of witnesses contradicting themselves as to the position of the new moon. The latter shows that the month was established by actually seeing the new moon and not by calculation. See Weiser and Krinsky. Leap years¹¹Of which there are seven in an 19 year cycle. come close to compensating for the additional days which a solar year has over a lunar year.¹²The solar year is about ten days longer than the lunar year. The extra month added during the leap year comes very close to closing this gap. The latter does not follow the way of the ancients.¹³Who established the new moon visually, not by calculation. The calculation¹⁴Of the fixed calendar. What follows is a bit complicated. Hence a few words are in order. The Jewish months begin with the conjunction of the sun and moon. The calculation starts with the very first conjunction. That conjunction theoretically occurred at the end of five hours and 204 parts of an hour of the second day of the week (the rabbis divided an hour into 1,080 parts). The latter is known as molad tohu, or molad baharad, which is the Hebrew abbreviation for five hours and 204 parts of an hour of the second day of the week. How do we arrive at this calculation? Ibn Ezra explains that we do so by counting back a year from the conjunction which occurred on the day that Adam was born. It should be noted that that year, except for the five days preceding the birth of Adam, did not exist in reality. It was a theoretical year. starts with the end of 14 hours of the sixth day;¹⁵Adam was born on Friday. That day was the first day of the month of Tishri. According to the rabbis the moon was then in conjunction with the sun at the end of 14 hours of the day. that is, add four days, eight hours, and 876 parts¹⁶The days between the start of one simple lunar year to the next lunar year. See Maimonides, M.T., Laws of the Sanctification of the New Moon, 6:4,5. to five hours and 204 parts of an hour of the second day of the week.¹⁷There were five days preceding the birth of Adam. Those days belonged to the previous year. In that year the conjunction of the sun and the moon (had they existed) would have taken place at five hours plus 204 parts of on hour of the second day. The calculation is as follows. A lunar month consists of 29 days, 12 hours, 44 minutes, and 3 1/3 seconds. A year consists of 12 months. If we work backwards from the birth of Adam, who was born on a Friday, a day which we mark as the New Year, then the previous New Year which came 12 months earlier had to fall on a Monday. For 12 times 29 1/2 days and 44 minutes comes to 50 weeks plus four days and some five hours. Then the birth of the new moon will occur at the end of 14 hours of the sixth day.¹⁸Adam was born on a Friday. The day of Adam’s birth started a new year. A year is added,¹⁹To the year which started with the birth of Adam. for we start counting from five hours and 204 parts of an hour of the second day of the week²⁰Of the “year” which preceded the birth of Adam. because of the five days which preceded the creation of Adam, for a day into a year is considered a year.²¹The five days preceding the birth of Adam count as part of a separate year. This presents no problem.²²To the calculation of the calendar. You cannot add an additional year,²³To the year preceding the birth of Adam and declare the year in which Adam was born a leap year. I.E.’s point is that our calendar is accurate. It is based on a 19-year cycle. The 3rd, 6th, 8th, 11th, 14th, 17th, and 19th year of the cycle are leap years. In those years we add a second month of Adar. According to current calculations the first leap year occurred a year after Adam was born (the third year from creation). If we begin the calendar two years before Adam was born, our calendar would have to be accordingly readjusted. However, we cannot do so, for there was nothing in existence two years before Adam’s birth. Hence the calendar must begin a year before the birth of Adam, not before. for it did not yet exist. Note, an additional month was added to the year after a year and a half.²⁴A real year and a half following the birth of Adam, for that was the “third” year from creation. The three years are calculated as follows. The “year” of tohu (or yetizrah, creation), the year in which Adam was born (molad adam), and a half of the following year. The intercalation is based on the average²⁵“The moment that the moon would have the same longitude as the sun, if both moved uniformly” (W.M. Feldman, Rabbinical Mathematics and Astronomy, p. 123). Also see Maimonides, M.T., Laws of the Sanctification of the New Moon, 6:1. The length of a junction varies. Its average time is 29 days, 12 hours, 44 minutes, and 3 and 1/3 seconds. The average movement (or conjunction) stands in contrast to the true conjunction of the sun and moon. movement of the moon.²⁶The average conjunction of the moon and sun. The sages therefore said that sometimes the birth of the moon comes at longer intervals; at times it comes at shorter intervals.²⁷Rosh Ha-Shanah 25a. The establishment of the month²⁸In the post-calendar period. is not tied to the sighting of the moon in Jerusalem,²⁹In the post-calendar period the month is established by calculation, not by the actual sighting of the new moon. or in the far east,³⁰Literally, edge of the east. During the Middle Ages, before the Western Hemisphere was discovered, the Jews, in common with others, believed half of the globe to be covered by water (the Great Ocean) and the other half to be dry and habitable. Thus R. Abraham bar Chiya of the 11th century begins his work on the Jewish Calendar by stating that “the earth is round like a sphere. The water of the Great Ocean covers half of it, which is uninhabitable, the other half is dry and habitable” (W.M. Feldman, Rabbinical Mathematics and Astronomy, p. 104). or in the west [of the world].³¹That is, to the actual sighting of the new moon at the edge of the East or the West of the world. The place of the average conjunction of the moon³²Which determines the start of the new year. is proof of this,³³That the new moon is not contingent on the actual sighting of the new moon at the edge of the East or the West of the world. for look, it is reckoned when occurring over Jerusalem.³⁴The new moon begins when it is calculated that the moon would be in conjunction with the sun over Jerusalem if both moved uniformly. Furthermore, we have seen the moon many times on the second night of the month of Nisan. It was similarly seen in the entire world. However, the month was established on the third night [of the week].³⁵If the new moon were based on sighting the moon, then the month would be established when the moon was actually seen. The same thing happened in the three months preceding Nisan. This occurs when the birth of the new moon of Tishri occurs at nine hours and 204 parts of an hour of the third day [of the week].³⁶On an ordinary year, that is, not a leap year. It was enacted³⁷By those who established the calendar. because of the postponement.³⁸Hebrew, dechiyot. “There are five separate occasions which necessitate the postponement of New Year’s day by one or even two days,” Feldman, op. cit, p. 191. For these dechiyot, see Maimonides, M.T., Laws of the Sanctification of the New Moon, Chap. 7. Also see Feldman, pp. 191-194. There are also times when the month of Tishri was established on the fifth day [of the week] and the moon was not seen on the night of the Sabbath. Now, the air was then clear. This occurs every year when the birth of the new moon³⁹In the month of Tishri. is close to half of the day⁴⁰Another example of a postponement. This postponement is called dechiyat yach (yod chet = 18), i.e., the 18th hour. “If the molad of Tishri occurs at or past noon (i.e., the 18th hour of any day. Noon is the 18th hour of a day which consists of 12 hours of daylight and 12 hours of night. Such a day begins at 6:00 P.M. New Year (Rosh Ha-Shanah) is postponed to the following day. Such a molad is called an Old Molad (molad zaken) because on the day of the new month, the moon is already old” (Feldman, pp. 191,192). and the moon is in half of its sphere’s apogee. The establishment⁴¹Of the new month. is also not dependent on the time of the conjunction⁴²The true conjunction of the sun and the moon. of the sun and moon. It is not even dependent on their mean conjunction, for note, the conjunction⁴³The mean conjunction. of the sun and moon at 15 hours and 599 parts⁴⁴The printed editions read 204 parts. However, the commentaries point out that this is a scribal error. of the hour on the second day⁴⁵This is known as dechiyat betutkapat (bet, tet-vav, tav-kof, peh-tet), which stands for two days, 15 hours, 599 parts. and similarly the conjunction at nine hours and 204 parts of the third day⁴⁶This postponement is called dechiyat gatrad (gimel-tet, resh-dalet), which stands for three days, nine hours, 204 parts. is proof of this.⁴⁷That the new moon is not always contingent on the mean conjunction. If I did not want to go on at length I would explain the secret of the calculation of the calendar and the secret of the very difficult law, i.e., the rule regarding a moon born before midday.⁴⁸See Rosh Ha-Shanah 20b. The general principle is: our wise men, of blessed memory, transmitted to us the rule that we are to rely on the intercalated calendar in exile. We received the same from the mouth of the prophets. We cannot do anything better than it. The sages ruled that the festivals be observed for two days in the Diaspora because of uncertainty.⁴⁹Whether the Bet Din in Jerusalem declared the new month on the 30th or 31st day from the start of the previous month. This was in the time before the fixed calendar. Those who fast for two days in observance of Yom Kippur⁵⁰Because they want to start the month with the day that the moon is calculated to be in conjunction with the sun. They also keep the Rabbinic calendar. fast in vain⁵¹They fast an extra day in vain. I.E. will point out that one should follow Rabbinic law with regard to the calendar. Thus if the rabbis say that one does not have to fast for two days to ensure that one fasts on the true Yom Kippur, it is not necessary to do so. See I.E., Sefer Ha-Ibbur, pp. 11,12. due to the “postponements.” For in a year when the birth of the new moon⁵²Of Tishri. occurs at nine hours and 204 parts of the hour on the third day of the week, they should fast on what is the eighth day of the month according to our calculation if they rely on the conjunction.⁵³For in this instance the first day of the month falls two days after the birth of the new moon. The point is that those who fast for two days do so because they want to be certain that they observed Yom Kippur on the real astronomical day. However, in a year when the birth of the new moon of the month of Tishri in an ordinary year occurs at nine hours and 204 parts of the third day, the new month should begin on Tuesday, not Thursday as in the intercalated calendar. However, since these people want to be certain that they celebrate Yom Kippur ten days from the start of the “real” New Year they should fast on what is the 8th day of the month according to the intercalated calendar. Why⁵⁴According to those who fast two days on Yom Kippur because of doubt. manipulate the date of the start of one year⁵⁵Literally, why should we pervert the calculation of our year? because of another year?⁵⁶The start of the new year is postponed when the birth of the new moon in the month of Tishri occurs at nine hours and 204 parts of an hour on Tuesday so that there not be a difference of six days between that year and the next. See Maimonides, Hilchot Kiddush Ha-Chodesh 7:4. Those who fast for two days believe that our festivals should be based on astronomical reality. If that is the case, then all the rules of establishing the calendar should be discarded. This would happen to them⁵⁷They would have to fast on what is the eighth day of the month according to our calculation in a year when the birth of the new moon occurs at nine hours and 204 parts of the third day. if the month is established by seeing the new moon.⁵⁸If they established the month by the actual sighting of the new moon and not only by calculating the birth of the new moon.