Astronomical Accuracy or a Grab for Power?

The Jewish Controversy about Calendar Postponements

[Saadia's controversy with Ben Meir about Hebrew calendar postponements in 921 C.E. (A.D.) mirrors modern arguments in which a power struggle is disguised as a concern about calendar computation for new moons, months, years, Holydays and Feasts involving luni-solar approximation. Remember: "The Calendar was made for man, not man for the Calendar!"]

From "Saadia Gaon: His Life and Works" by Henry Malter, Philadelphia: The Jewish Publication Society of America. 1921. Chapter IV. Saadia's Controversy with Ben Meir. pp. 70-88

"I should prefer to escape discussion of a subject that ranks as one of the obscurest and most complicated in Jewish literature. Besides, the origin and history of the Jewish calendar does not readily lend itself to a popular presentation. Our purpose here will be served best by a brief summary of principles, avoiding as far as possible the details of computation.

It is generally accepted that the Jewish festivals were, in Biblical times, fixed by observation of both the sun and the moon. Gradually, certain astronomical rules were also brought into requisition, primarily as a test, corroborating or refuting the testimony of observation. Such rules are mentioned for the first time in the Book of Enoch, in the Book of Jubilees, in the Mishnah, and later in the two Talmudim [Babylonian and Jerusalem]. It has been authoritatively proved that in spite of a more advanced knowledge of astronomy the practice of fixing the new moon and the festivals by observation was in force as late as the latter part of the fifth century [C.E., A.D.]. The right to announce the new moon after receiving and testing the witnesses who had observed its appearance was the prerogative of the Palestinian Patriarchs, and the repeated attempts of the authorities in Babylonia to arrogate this right unto themselves were promptly frustrated by interdicts from Palestine. With the beginning of the fourth century, however, Palestine, owing to the terrible persecutions suffered at the hands of the Romans, gradually ceased to be the spiritual center of Jewry. Babylonia, where better conditions prevailed under the Persian rule, took its place, and the religious right to fix the calendar likewise passed over to the heads of its flourishing academies, though not without protests from Palestine. In Babylonia also, the practice of observation was continued until the time of the last Amoraim, although a practical system of reckoning had been known to scholars for more than a century. It was only after the close of the Babylonian Talmud, in the sixth or perhaps later, in the seventh century, that the observation of the moon was entirely given up, and a complete and final system of calendation introduced. This was adopted by all the Jews of the Diaspora, and has been accepted as binding down to the present day.

The real originators of this calendar as well as the circumstances under which it was enforced are lost in the general obscurity of the history of the Oriental Jews during the first two centuries after the completion of the Talmud.

According to a Babylonian [Jewish] tradition of Gaonic times, it was Hillel II (in the IVth Century C.E.) who fixed the Jewish calendar and established its rules. However, these rules of Hillel II were only one phase in the history of the Jewish calendar, which was not completed before the sixth-seventh century. (Hayyim Schauss (1938) The Jewish Festivals, Cincinnati: Union of American Hebrew Congregations, n.121, p.299)
It is certain, however, that the whole system of calendation, although promulgated in Babylonia, originated in Palestine. There are indications that the Palestinian Jews felt sore at heart that they had to bow to the Babylonian authorities, whom they must have considered as usurpers of their inherited rights, and from time to time they must have tried to re-establish their lost authority, but in vain.

With the beginning of the tenth century the situation was again changed. The once flourishing Babylonian academies of Sura and Pumbedita, especially the former, owing to general conditions and to the lack of strong leaders, began to show a marked decline, so that the Sura academy was on the point of closing its doors, and the sister-academy in Pumbedita was greatly reduced in strength by a bitter struggle between its leading scholars and a pugnacious exilarch. At this juncture a man of marked ability arose in Palestine, who, recognizing the propitious moment, sought to take advantage of the situation in order to restore its former prerogatives to his country.148 This man was [Aaron ?] Ben Meir, a Palestinian [Jew] by birth and the head of a school in his native land. He claimed to be a descendant of the Patriarchs of the house of Hillel, mentioning particularly R. Gamliel and R. Judah Hanasi as his progenitors. With genuine scholarly attainments and considerable facility in writing he combined strong will and determined character; all of which gained for him great influence even outside of Palestine.

In order to bring out Ben Meir's point of view it is necessary to explain some of the elementary rules of the Jewish calendar:

The Jewish lunar year consists of twelve alternating months, of 29 or 30 days, respectively. Such a year, counting 354 days, is called normal or regular. For certain reasons, to be explained presently, the year is sometimes made to count only 353 days, in which case it is designated as deficient; or a day is added, making 355, and then it is called full. To make a year full or deficient, the months of Heshwan and Kislew (approximately November and December) were selected for the necessary addition or subtraction. In a regular year Heshwan always counts 29 and Kislew 30 days (=59); in a full year a day is added to Heshwan ( =60), and in a deficient year a day is subtracted from Kislew ( = 58). Whether a year is to be declared regular, full, or deficient depends upon four rules, called "Postponements," or the " Four Gates".151 These must be observed in the appointment of every Jewish New Year's day (first of Tishri, approximately September). We shall here mention only the two rules necessary for the understanding of Ben Meir's attempted reform.

The first of these rules is that New Year's day should never be appointed on either a Sunday, or Wednesday, or Friday. Sunday is considered unfit, because with Rosh ha-Shanah falling thereon, the seventh day of the Feast of Tabernacles (Hosha'na Rabbah) on which the ceremony of "beating the willow-twigs" is an important part of the service, would fall on the Sabbath, and the observance of the ceremony could not be permitted. Wednesday and Friday are likewise inadmissible, because the Day of Atonement would then, to the great inconvenience of the people, fall on either Friday or Sunday immediately before or after the Sabbath. If, therefore, the new moon of the month of Tishri was observed in the night preceding one of these three days (Sunday, Wednesday, Friday), New-Year was proclaimed on the day following; a custom still in force now that calculation has been substituted for observation, the calendar having been fixed in agreement with this rule of Talmudic origin [tractate Rosh ha-Shanah 20a].

The second rule is that in order to proclaim a New-Year's Day it is necessary that the new moon be seen before noon of this day. If the new moon is not observed until exact noon, or later, no matter on what day of the week, the New Year has to be postponed to the following day. If that happens to be one of the three days declared inadmissible for Rosh ha-Shanah, the festival is of course postponed for two days. The supposed reason for this rule is that it takes fully six hours from the moment the new moon is caught sight of from some place of vantage until it becomes again visible. Now if the conjunction (Molad), that is the meeting of the moon and the sun in the same degree of the zodiac, takes place at 12 (noon) sharp, or still later, there is no chance for the moon to become visible until sunset (six o'clock), when the Jewish astronomical day is considered over. In strictness, this rule (which is also Talmudic, [tractate Rosh ha- Shanah 20b]), has pertinence only to a system depending on observation; but, as stated before, the rules of calendric calculation were made to agree with the original rules of practice though the reasons given may have lost their value.

It will be readily understood from the above that whenever New Year is postponed, the year is made shorter, being reduced to 353 days and thus turned into a deficient year. The month of Tishri, however, is not made to suffer by this reduction. As stated before, the two days are taken off from the next following months, Heshwan and Kislew which are made to count only twenty-nine days each. To use the technical term, they are both made deficient. It may be added to complete our survey that to bring the solar year and the lunar year into coincidence in a certain cycle (19 years), an intercalary month is inserted into the Jewish year at necessary periods, making a leap year of 383 to 385 days.

When observation was replaced by calculation, the calendar did not, indeed, have to be fixed by the authorities from year to year. Anybody familiar with the rules on which it was based could determine many years ahead on what day of the week New Year or any other festival would fall in a given year. In fact it was most essential to know, in order to arrange the calendar for any year, on what day Rosh ha-Shanah would fall two years later.

In the year 4681 of the Jewish era (=921 common era) it was anticipated that in the year 4684 (September, 923) the rule of two days' postponement, described above, would come into operation. Calculation showed that if observation had been still in practice, the new moon of Tishri could not be observed till about thirteen or fourteen minutes after meridian on the Sabbath. Consequently the accepted rules required, observation or no observation, that New Year be postponed to Monday. Now, it must be borne in mind that there is a difference of four, occasionally of five, or even of six days (leaving fractions out of consideration) between two successive years. That is to say, the festivals of a given year fall from four to six days later in the week than those of the preceding year. This is due to the fact that fifty weeks of the regular common year and fifty-four weeks of the regular leap year contain, the first only 350, and the second 378 days, while a complete year of twelve regular months counting alternately twenty-nine and thirty days, contains 354 days, and thirteen such months make a year of 384 days. If therefore in 923, the year under consideration, New Year was to fall on Monday, Rosh ha-Shanah of the previous year (922) must take place four days earlier, i.e., on Thursday. Again, in 922 New Year had to be approximately six days later than in 921, because the year 921 happened to be a leap [intercalary] year. This would bring New Year of 921 on Friday; but as Friday had been declared unfit, Thursday had to be substituted. To sum up:
the accepted order of the calendar in those three years was as follows:
In 4682 (921/22) New Year on Thursday, the Year full (385 days, because it was leap year, 355 + 30), that is Heshwan and Kislew containing each thirty days, and Passover (which is also to be mentioned for reasons that will become obvious later), falling on a Tuesday.
In 4683 (922/23) New Year on Thursday, the year regular (354 days), Heshwan and Kislew counting together 59 days (29+30), and Passover on Sabbath.
In 4684 (923/24) New Year Monday (Postponement), the year deficient (353 days), Heshwan and Kislew counting together fifty-eight days (29+29), and Passover on Tuesday.

We may now return to Ben Meir, but for a full understanding of his position it is necessary to mention one more point, namely that in the system of the Jewish calendar the hour is divided not into 3600 seconds but into 1080 halakim (parts).

As a learned man, the head of an academy, Ben Meir was naturally well informed on the question of the Jewish calendar. The four principal rules of calendation had been known for centuries, and in the main he recognized them as binding. All that he apparently asked, when he began the controversy, was a modification of the rule which required that to proclaim any day as Rosh Hodesh [first of a month] the new moon must be discovered (or, in times of reckoning, be due to appear) before noon. Following either another computation or a definite Palestinian tradition, he added 642 "parts" (about thirty-five minutes) to the time limit, so that if, for instance, the new moon of Tishri was due to appear on the Sabbath at noon or within the 642 halakim after noon, no postponement should take place. The Sabbath would thus be declared Rosh ha-Shanah, while according to the accepted calendar the festival had to be postponed until Monday (Sabbath being ineligible on account of the belated appearance of the new moon, and Sunday on account of rule I).

This being precisely what was due to happen in Tishri of the year 4684 (September 923), Ben Meir, believing the time favorable for the long-sought overthrow of the Babylonian authority came out in the summer of 4681 (921) with the declaration that Heshwan and Kislew of the ensuing year (4682=November and December 921) should both be made deficient. Now the year 4682 could be declared deficient only when the year 4684 was to be declared full; that is, if Rosh ha-Shanah of the last named year was not to be postponed on account of a belated new moon, but was to take place on the Sabbath of the new moon's appearance. In fact it was the anticipated postponement of the New Year of 4684 which Ben Meir attacked. He contended that inasmuch as in that year the new moon was due only 237 halakim (about fourteen minutes) after midday and thus much in advance of the allowed 642 parts, it was not to be considered as late, and hence no postponement could be admissible.

Ben Meir's order for the three years was accordingly:
4682: New Year Thursday, deficient, Passover Sunday;
4683: New Year Tuesday, regular, Passover Thursday;
4684: New Year Saturday, full, Passover Tuesday.

Such, and apparently so technical if not trivial, was the actual issue between Ben Meir and Babylon.

The question forces itself upon us: What was Ben Meir's reason for the addition of 642 parts to the given time limit? It is hardly credible that a learned and pious man, as Ben Meir undoubtedly was, should have undertaken to change essentially one of the most sacred religious institutions of the Jewish people, one upon which depended the celebration of the festivals in their proper season, unless there were strong reasons to justify his action.158 Moreover, it would have been the most injudicious step for a leader to take, as he could foresee that no conscientious Jew would follow him, unless the religious expediency of his procedure was proved. As a matter of fact, many Jewish communities in Palestine and outside159 accepted Ben Meir's view, and soon after were ready to celebrate, or actually did celebrate, the Passover of the year 4682 on Sunday instead of Tuesday.

Various views have been advanced in explanation of the matter; among them that the accepted calendar being based on the time in the city of Babylon, where noon is approximately 56 minutes earlier than in Jerusalem, Ben Meir, claiming Jerusalem as the right basis, added 642 parts (35 minutes) partly to offset the difference. Against this it has been properly pointed out that the fixing of the calendar was originally the prerogative of Palestine, and it is therefore inconceivable that it should have been based on Babylonian time. Nor is there any proof that later Babylonian authorities assumed to transfer the basis from Jerusalem to Babylon. Besides, if this was the reason for the addition, Ben Meir would certainly not have failed to mention it. Finally, the addition of precisely 642 parts (35 minutes instead of 56) would after all be an arbitrary and futile act.

Another, more acceptable explanation is that Ben Meir's real purpose was to reduce the number of postponements provided for in the accepted calendar. These postponements were, in his opinion, frequently the cause of celebrating the festivals at a time other than that prescribed in the Torah. Most of them resulted from the rule concerning the belated new moon, and when this operated in connection with another rule, it might readily necessitate a postponement for two days. Finding that a slight extension of the time set for the appearance of the moon around mid-day would greatly reduce the number of such postponements, he considered it a religious duty to issue a proclamation to this effect. The claim that the rule opposed by him was based on the authority of the Talmud did not appeal to Ben Meir, as the passage in question is rather obscure and allows of differing interpretations.

Plausible as this explanation seems to be, it is still difficult to see why he should have selected exactly the number of 642 for his addition, and the suggestion has therefore been made that in this respect Ben Meir relied on a definite Palestinian tradition. Various passages in the controversial letters dealing with the subject seem to support this view. It is quite possible that others before Ben Meir had attempted to rectify the calendar by the same addition of 642 parts, but that the literary records, if there were such, have not been preserved.

At this point the subject of the calendar may be dismissed, and we may revert to the discussion of the course of events connected therewith, which led to the defeat of Ben Meir and ultimately to the rise of Saadia to the Gaonate.

Ben Meir's intention to make Heshwan and Kislew of the year 4682 deficient and to have the Passover of the same year celebrated two days earlier than that fixed by the Babylonian authorities (Sunday instead of Tuesday) became known in the summer of the year 4681 (921). In what way he had manifested this intention cannot be ascertained from the available material. At that time it seems he had not yet issued an official proclamation. The rumor reached Saadia in Aleppo. He at once addressed several letters to Ben Meir, demonstrating to him the correctness of the established calendar and warning him against the change advocated. This is reported by Saadia himself in the two letters which he addressed during the subsequent winter to his pupils in Egypt. He further informs us, in the same letters, that in Bagdad, whither he had gone from Aleppo, he learned that his repeated warnings had had no effect on Ben Meir, who had meantime issued his official proclamation, much to the perturbation of the Babylonian Geonim. The date of Ben Meir's proclamation is not given by Saadia. In all probability it was issued on Hosha'na Rabbah (the seventh day of the Feast of Tabernacles) in the year 4682 (autumn, 921), on which day, as is known from other sources, it was customary among the Palestinian Jews of that period to assemble annually on the Mount of Olives (east of Jerusalem) for prayer and solemn processions around the mount (Hakkafot). The occasion was used for the discussion of the various religious communal needs of the people, and decisions as to future actions were adopted.

As soon as the news of this proclamation reached Babylon the Exilarch David ben Zakkai, in conjunction with the Geonim of both academies and probably also Saadia, addressed an official letter to Ben Meir setting forth in urgent words the validity of the established calendar and warning him against the contemplated change. At the same time the Geonim sent out circular letters to the various Jewish communities, advising them to abide by the old order, and not to heed the innovations proposed.

It was about this period that Saadia wrote to his Egyptian pupils. The first half of his letter was given above (pp. 55 f.); the second reads as follows:

"Know that when I was yet in Aleppo, some pupils came from Ba'al al Gad [a town at the foot of the Lebanon mountains] and brought the news that Ben Meir intends to proclaim Heshwan and Kislew deficient. I did not believe it, but as a precaution I wrote to him in the summer [not to do so]. The Exilarch, the heads of the academies, all the 'Allufim [senior scholars], teachers and scholars, likewise agreed to proclaim Heshwan and Kislew full, and that Passover be celebrated on Thursday. In conjunction with their letters I too wrote to most of the great cities, in order to fulfill my duty. Persist ye also in this matter and close up this breach, and do not rebel against the command of God. None of the people dare to profane the festivals of God wilfully, to eat leavened bread on Passover, and eat, drink, and work on the Day of Atonement. May it be the will [of the Lord] that there be no stumbling-block and no pitfall in your place or in any other place in Israel. Pray, answer this letter and tell me all your affairs and your well-being. May your our peace grow and increase forever!"

Here we have Saadia's own testimony as to the part he took in the struggle, and the rank to which he had attained among the Babylonian authorities at this period. Not only did they invite his co-operation in signing their official letters in order to confer special weight upon their ordinances, but Saadia issued such letters on his own account to the largest congregations in and outside of Babylon - a proof of the great fame and popularity he must have enjoyed in Jewry in general.

Meanwhile Ben Meir, far from heeding the interdicts of Babylonia, repeated his attack by sending his son to Jerusalem, to proclaim there, for the second time, the proposed changes of the calendar. To the charges of the Geonim and of Saadia he replied in a disrespectful and aggressive tone, denying their authority in matters of the calendar, which, he claimed, should be left, as in former times, in the hands of Palestinian scholars. In a lengthy letter to his adherents in Babylonia, in which he sets forth with much detail the reasons for his reforms, he pours out his whole wrath on Saadia in particular, denouncing him and "his arrogant followers" in scathing terms. This is also significant of the role Saadia evidently played in the affair. In the meantime the feast of Passover was approaching. The congregations were bewildered by commands and countermands. Some prepared to celebrate the festival on the date set by Ben Meir, others stood up for the accepted calendar. A serious rupture was imminent in the ranks of Jewry, not dissimilar to that brought about previously by the Karaites. Saadia again addressed a letter to his pupils in Egypt, and probably also to various communities elsewhere imploring them to remain steadfast and to abide by the regulations of the Geonim. To his credit it must be remarked that in this letter there is not a single harsh word against Ben Meir, the originator of all the trouble.

The repeated notes of warning did not bring about the desired result. Most of the Palestinian and some of the Babylonian communities actually celebrated that Passover, and consequently the other festivals, two days earlier than the official date. The schism must have assumed alarming proportions. Even a non-Jewish historian of the following century considered it important enough to include it in his account of historical events. Twice more, so far as our records give us information, the Babylonian representatives of Judaism expostulated with Ben Meir. This happened in the ensuing summer. Again letters of warning and exhortation were sent to the "divided house of Israel," but to no effect. "The two parties indulged in mutual recriminations and excommunications, and even went so far as to charge one another with fraud and deception."181 How long the quarrel lasted, and by what means it was brought to an end, cannot be learned from the scanty material that was discovered in the Genizah [storage room under an old Cairo synagogue]. From the report of the Syrian historian and from Karaitic sources we know only that at the beginning of the year 4683 the quarrel was still in progress. Rosh ha-Shanah of that year was observed by the two opposing parties on different days in accordance with their divergent views.

We know, however, that Ben Meir and his supporters ultimately met with crushing defeat, and as may be plainly seen from Ben Meir's epistles, he attributed his downfall particularly to the activity of Saadia. Ben Meir's judgment was doubtless right on this point. Neither the Geonim who presided over the two academies, nor any of the scholars among their followers had either the intellectual capacity or the complete command over the people to parry the determined onslaught of Ben Meir, whose influence reached far beyond the boundaries of his own country and whose contention was not without merit. In fact, it was partly because of the weakened standing of the Gaonate that Ben Meir could venture to assert his authority above that of Babylonia. But Saadia's fiery genius, his profound learning, and above all his superior literary skill proved more than a match for his opponent and finally brought about Ben Meir's overthrow.

It is characteristic of the situation, that, as Saadia himself tells us, the Babylonian authorities, having failed in all their efforts against the disturber, had thought of calling the government to their assistance. For some reason not stated they gave up the plan and decided upon issuing a memorial-volume (Sefer ha-Zikkaron) [of which only fragments remain], in which all the misdeeds of Ben Meir from the beginning of the controversy to its end, his errors in calculation, the proceedings of the Gaonate against him, and particularly the reasons for their continued upholding of the accepted calendar, were to be minutely recorded. The volume was to be spread broadcast among all the Jews of the Diaspora with the special injunction, that it be read annually in public on the twentieth of 'Elul, before the approach of the high Holy Days, and thus serve as a warning against possible upheavals of a similar nature in all future generations. It was again Saadia who was charged with the composition of this important document. He wrote the book in the summer of 4682 (922) while the struggle was at its height. It was read publicly, as provided, in the month of 'Elul of the same year. Its effect on the communities was very great, apparently putting an end to the agitation, which had lasted for nearly two years. At all events, nothing more is heard of Ben Meir during the following years, though his main intention was to change the date of Rosh ha-Shanah of the year 4684 (923).

How important a part Saadia had in the regulation of the present calendar can be seen also from the fact that eminent authorities of later centuries [Tosafist Jacob Tam] describe him as the father and founder of the science of the calendar. Most, if not all, of his work in this field was done in connection with the controversy with Ben Meir or his polemics with the Karaites. Its contemporary importance may be judged from the fact that it paved the way to Saadia's election to the Gaonate; but the lasting moment of Saadia for the Jewish world and his influence on the development of medieval Jewish literature have a better basis than his discomfiture of Ben Meir. Considering the acrimony - almost ferocity - with which the quarrel over the calendar was carried on by both controversialists,188 especially in the last stages of the argument, one cannot but designate it as a deplorable episode.


Notes: (omitted notes only contain references to sources)

148. Epstein presents the matter as if Ben Meir's motives in starting the conflict were purely scientific, that he tried to rectify what he considered erroneous in the established calendar. This view can be accepted only with great reservation. For whatever the merits of Ben Meir's calculation may have been, there is no doubt that his personal ambition and perhaps still more, his desire to reassert the authority of the Holy Land, played, consciously or unconsciously, a very important part in his contention. More than once in his letters he emphatically denies to the Babylonians the right to fix the calendar, which, he constantly reiterates, is the exclusive prerogative of his country; comp, below, note 158.
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151. The Four Rules, for which see Ginzel, II, 9I f., are found together in a writing called "The Four Gates", because it treats of the four days of the week (Monday, Tuesday, Thursday, and Saturday), on which alone Rosh ha-Shanah is allowed to fall, the days forming thus, as it were, the gates through which we enter into the respective new year. The original work, of which the Four Gates formed a part, is lost. Nor can it be ascertained when and where or by whom it was composed. From the Ben Meir controversy we can see that as early as the beginning of the tenth century its authority was generally recognized. A certain Jose Al-Nahrawani probably a contemporary of Saadia, versified that part of the work which dealt with the Four Rules, and his versification also bears the same name. Steinschneider discovered the work of Jose in a MS. at the Bodleian library, written in 1203, and published it in the periodical Kerem Chemed IX (1856), 41. A. Epstein re-edited the same with copious notes in the REJ., XLII (1901), 204-210. At the same time a commentary on Genesis and Exodus by Menahem b. Solomon (12th century) was published by S. Buber (Berlin, 1901), wherein a different recension, of Palestinian origin, is found in connection with the verse Exod., 12, 2 (vol. II, 90-92).
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158. Ben Meir guards himself against the reproach that his desire to re-establish the authority of the Holy Land was the only reason for his reforms, by pointing out to his opponents the correctness of his calculation; comp. note 148.
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159. As may he seen from a letter of Saadia to three Rabbis in Egypt, published by Hirschfeld, JQR., XVI, 290-297, the Egyptian Communities too, or at least some of them, during the time of the quarrel celebrated the festivals according to the computation of Ben Meir.
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181. Poznanski JQR., X, 154, based on the testimony of the Karaite Sahl b. Mazliah.
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188. Ben Meir's letters abound in personal denunciations and abuses of Saadia, which reveal the extreme bitterness of the writer. Not satisfied with the attacks on the character of his opponent, Ben Meir tried to defame also Saadia's family, asserting, as he says, "on good authority " that the latter's father was a Muezzin in the service of the Muhammedans, defiled himself by eating abominations, until he was driven out of Egypt and died in Jaffa. Saadia retaliates by adorning Ben Meir with the epithets "the obscurantist," and "the accursed one," both in satiric allusion to the name "Meir". Ben Meir's sons he terms "calves".
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Omitted notes refer the reader chiefly to:


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