Some Thoughts on the Issue of Calendars

By Tim Hegg


The study of calendars from the Ancient Near East is fraught with difficulties. Not only are there wide divergencies between calendars, but we often lack sufficient data that plainly describe how various calendars were constructed and put into practice. Even when we narrow our study to calendrical issues of pre-destruction Judaisms in the Land of Israel, we still face formidable challenges in understanding to what extent the debates over calendar issues actually separated various Jewish sects in terms of their actual practice. We do know that the Qumran sect separated geographically from Jerusalem for a number of reasons, one of which was calendrical disputes.

Obviously, in this short essay, I am making no attempt at an exhaustive investigation into the many calendar issues that existed among the Judaisms of the pre-destruction era. Rather, I’m simply offering a few thoughts which I think might be helpful for those who are investigating the question of which calendar should be used when seeking to determine when to celebrate the biblical festivals.

How was the 1st day of the 1st month (later called Nisan) determined in 1st Century Israel?

The primary issue which the Jewish community faced when seeking to determine the “appointed times of Adonai” (מוֹעֲדֵי יהוה, mo’adei Adonai) was how to decide when the first month of the year began. Not only did the yearly festival cycle begin in the first month (the month in which Pesach occurs), but once this month was determined, all of the remaining festivals in that year were likewise set in place. The question of when the first month was to begin relates to the fact (as we shall see) that months in the Hebrew calendar were determined by the phases of the moon. Yet certain festivals (such as Pesach) are specifically commanded to be celebrated in the Spring. The seasons (תְּקוּפוֹת, tequfot) are not set by the moon but by the sun. Thus the lunar cycle, which governed the months, had to be intercalated in order to remain synchronized with the solar year. This was done by adding a 13th month (Adar II) when needed. That, of course, became the issue: how was the Jewish community to determine when and when not to add a 13th month? As we shall see, the rabbinic literature1 indicates that the intercalation of the year was based more upon practical rather than astrological factors, though surely astrological factors were important.

One thing we know for certain: no extant data exists which inform us as to which years in the pre-destruction era were intercalated with a 13th month. This being the case, all attempts at pinpointing the exact year of Yeshua’s crucifixion by astrological calculations are doomed to failure. The same may be said for those who think that the “priestly courses” (מִשְׁמָרוֹת, mishmarot) can be used to determine the month in which Yeshua was born, based upon the service of Zacharias (who was of the division of Abijah, Lk 1:5) in the Temple when an angel announced that his wife, Elizabeth, would be with child. The text goes on to indicate that it was in the sixth month of her pregnancy that Mary, a relative of Elizabeth, received the news that she would be the mother of the Messiah. Once again, if there were data for us to know which years were intercalated with a 13th month, then we might be able to know the month in which Yeshua was conceived and thus in which month He was born. But the lack of any data relative to which years were intercalated makes such a determination impossible.

Throughout the Torah, the months are referred to by numerical order, e.g., first month, second month, and so on. The month names Ziv,2 Bul,3 and Ethanim4 are Canaanite names of months and are found only in 1Kings 6–8 in connection to Solomon’s building of the Temple. We may surmise that they are used in this section of Scripture because Solomon was in communication with the surrounding nations to obtain building materials for the Temple. The term Abib (אָבִיו) is only found in the Torah, and most likely is not a Canaanite month name. The reason why it is most likely not the name of a month in the Canaanite culture is because it is always found with the article (הָאָבִיב), 5 a construction which does not generally occur with proper names. In cognate Semitic languages (Arabic, Aramaic, Canaanite) the word means “ears of corn already ripe” and came to mean “the time when the ears of corn become ripe.” In the Torah it is always used with the word “month” (חֹדֶשׁ) and means “the month when the grain ripens,” and particularly, when the barley ripens (since the barely is the first crop to ripen in the Land).

The month names of the post-exilic Hebrew calendar are of Babylonian origin, no doubt having become commonly used while Israel was in exile there. Thus, post-exilic books of the Tanach mention the months of Adar,6 Nisan,7 Shebat,8 Chislev,9 Elul,10 Tevet,11 and Sivan.12 An early rabbinic source, Megilat Ta’anit, dated before the destruction of the Temple (70 CE), mentions all 12 of the Babylonian month names in order,13 giving at least some indication that they were in use during the 1st Century. Yet in the Apostolic Writings, months are referred to numerically, not by names.

While it has long been realized that the book of 1Enoch, along with the book of Jubilees, utilized a solar calendar (364-day year), it was only in the discovery of the Dead Sea Scrolls that scholars came to realize a 1st Century Jewish sect actually attempted to live by that calendar, or better, by a variation of that calendar. Uwe Glessmer has shown that, contrary to much earlier Dead Sea Scroll scholarship, the calendar(s) at Qumran can no longer be considered purely solar.

These considerations indicate that if a comprehensive heading for the concept of calendar at Qumran is to be chosen, the oft-used term “solar calendar” is certainly inappropriate and should be avoided.14

Rather, Glessmer concludes:

But in light of the manifold details now available to us, it has become increasingly evident that these ancient texts witness not to a monolithic, static phenomenon, but to a diverse growth and development.15

In general, one of the primary motivations for the alternate calendars found at Qumran as well as in 1Enoch and Jubilees is that the beginning of each year needed to fall on a Wednesday (יוֹם רְבִיעִי, fourth day) because the luminaries were created on the fourth day of the creation week. A second compelling motivation was the need to avoid having Festivals fall on the weekly sabbath.

With the recovery of the Qumran calendars, some have suggested that the solar calendar is, in fact, the ancient biblical calendar. But this viewpoint has a significant hurdle to cross: the Hebrew words for “month” are חֹדֶשׁ, chodesh16 and יֶרַח, y’rach,17 and both of these words derive from their connection with the Hebrew word for “moon,” יַרֵחֵ, yareach. The inescapable conclusion is that the ancient Hebrew calendar had its months reckoned by the moon and was not purely solar. Yet a strictly lunar calendar without reference to the four תְּקוּפוֹת, tekufot, “seasons” would quickly move the festivals out of their seasons so as to make impossible the prescription of the Torah that, for instance, Pesach is to be celebrated in the Spring (Deuteronomy 16:1).

Thus, the biblical calendar is solar-lunar, deriving the need for intercalation to adjust the lunar months to the solar year. The method of intercalating was, from ancient times, a source of debate, and we know that various methods did evolve.18 That there are indications in the biblical text of a calendar by which months could be known is evident, for Jonathan knows that “tomorrow” will be the new moon:

Then Jonathan said to him, “Tomorrow is the new moon, and you will be missed because your seat will be empty. (1Sam 20:18)

Apparently the month, in this case, was not set by a physical observance of the new moon but by a pre-arranged schedule or calendar, and one which must have been intercalated.

Yet we also know that the sighting of the new moon was practiced as the means of determining both the beginning of the first month (in which Pesach occurs) and the seventh month (in which Yom Teruah, Yom Kippur, and Sukkot occur).19

Why were these two months important as beginning points? The seventh month, called “Tishri” after the return from exile, is the month in which the Torah describes the turn of the year (בְּקוּפַת הַשָּׁנָה):

“You shall celebrate the Feast of Weeks, that is, the first fruits of the wheat harvest, and the Feast of Ingathering at the turn of the year. (Ex 34:22)

This is parallel to the language in Exodus 23:16 which refers to the “end of the year” (בְּצֵת הַשָּׁנָה). In this case, the Feast of Ingathering is the Festival of Sukkot, and the month in which it is celebrated is therefore the month which marks the turn of the year. It was for this reason that in ancient times the seventh month was considered to be the beginning of the year for crops, and most likely the demarcation for tithes of crops. The harvest, which marked the end of one agricultural season, is celebrated in the month of Ingathering which begins a new agricultural year. However, the Torah calls the month of Pesach the first month because it is the beginning of the festival cycle. Thus, the sighting of the new moon for each of these months was important for the intercalation of the calendar.

A month has been defined by the Sages as the period of time between one conjunction of the moon with the sun and the next. A conjunction of the moon with the sun is when the moon is directly between the earth and the sun and is therefore invisible.20 This conjunction is called מוֹלָד, molad in the Hebrew, from the verb ילד, to birth.” The length of time from one conjunction to the next is 29 days, 12 hours, 44 minutes, and 3.33 seconds.21 Since the solar year is 365 days, 48 minutes, and 46 seconds long, it exceeds a lunar year (of 12 months) by 11 days. The lunar year must therefore be intercalated in order to keep up with the solar year, since the celebration of the festivals is also tied to the seasons. If it were not intercalated, the festivals would “wander” through the year and eventually be out of season. The manner in which the lunar year is to be intercalated, however, is not specified in the Torah. From ancient times, however, it was the practice to add a month to the year (called Adar II after the exile) when deemed necessary, and this was eventually calculated to happen in each of seven years within a 19 year cycle.

The extant rabbinic literature recounts various discussion on and reasons for intercalating a given year. In Tosefta Sanhedrin 2.2, (repeated as a baraita in b.Sanhedrin 11b), which names Shimon b. Gamliel as an authority,22 three factors are cited in regard to intercalating the year: 1) whether the barley was ready for harvest (in relation to Pesach and the Torah commandment to wave the sheaf of barley, cf. Lev 23:11f), 2) whether the fruit had ripened (in relation to bringing the first-fruits of the tree at Shavuot, Ex 23:16), and 3) whether the month was in the correct season, i.e., the Spring equinox had occurred.

On account of three signs do they intercalate the year, because of the [premature state of] the grain, because of the condition of the produce of the tree, and because of the lateness of the spring equinox. On account of two of these they will intercalate the year, but on account of only one of them, they will not intercalate the year. But if they declared the year to be intercalated, lo, this is deemed intercalated. If the premature state of the grain was one of them, they would rejoice. R. Shimon b. Gamliel says, “Also on account of the lateness of the spring equinox.”23

Our Rabbis taught: A year may be intercalated on three grounds: on account of the premature state of the corn-crops; or that of the fruit-trees; or on account of the lateness of the Tekufah (season). Any two of these reasons can justify intercalation, but not one alone. All, however, are glad when the state of the spring-crop is one of them. Rabban Shimon b. Gamliel says: On account of [the lateness of] the Tekufah. The Schoolmen inquired: Did he mean to say that “on account of the [lateness of the] Tekufah” [being one of the two reasons], they rejoiced, or that the lateness of the Tekufah alone was adequate reason for intercalating the year? — The question remains undecided.24

The unresolved question whether Shimon b. Gamliel’s statement indicates that the lateness of the season was itself sufficient to intercalate the year would seem to indicate that the halachah was still being decided. Yet it is significant that this mishnah lists three factors that could cause a year to be intercalated, only one of which was astronomical.

The Tosefta (t.Sanhedrin 2.1ff), which is based upon m.Sanhedrin 1.2, also deals with what constitutes a legal and binding intercalation, and expands or amplifies the Mishnah’s statement:

“The sanctification of the new month and the intercalation of the year are to be done by three [judges],” the words of R. Meir. And the sages say, “Before three do they begin, and before five they debate the matter, and they reach a final decision with seven [judges]. (t.Sanhedrin 2.1)

The Tosefta goes on to explain that when there is a positive vote of two and against the negative of one, they add two more (thus five). If three vote positive and two negative, they add two more (thus seven) and reach the final decision with seven, which is the minimum for a quorum. It further notes that where a rabbi and his disciple (father and son) are part of the Beit Din (panel of judges), their vote counts as one.

The Tosefta, after quoting the Mishnah, adds that the evidence of conditions in three regions are used for the intercalation: Judea, Trans-Jordan, and Galilee, and that the evidence of any two is sought. Yet if the judges intercalate the year on the basis of one region only, it is valid.

Then the Tosefta deals with additional grounds for intercalating the year, which were not mentioned in the Mishnah:

They do not intercalate the year because the [season of the] kids, lambs, or pigeons has not yet come. But in the case of all of them, they regard it as support [for intercalating] the year. But if they declared the year to be intercalated [on their basis], lo, this is deemed intercalated. R. Yannai25 says in the name of R. Shimon b. Gamliel26 who said, “The pigeons are tender and the spring lambs thin, and it is proper in my view, so I have added thirty days to this year.” Rabban Gamliel and sages were in session on the steps of the Temple and Yohanan the scribe was before them. He said to him, “Write: ‘To our brethren, residents of Upper Galilee and residents of Lower Galilee, May your peace increase! I inform you that the time for the removal has come, to separate the tithes from the olive vats.’ ‘To our brethren, residents of the Upper South and residents of the Lower South, may your peace increase! We inform you that the time for the removal has come, to separate the tithes from the sheaves of grain.’ ‘To our brethren, residents of the Exile of Babylonia, and residents of the Exile of Media, and of all the other Exiles of Israel, may your peace increase! We inform you that the pigeons are still tender, the lambs are thin, and the spring-tide has not yet come. So it is proper in my view and in the view of my colleagues, and we have added thirty days to this year.’” (t.Sanhedrin 2.6)

Here we see that the tradition passed on to the post-destruction sages was that the year could be intercalated on the basis of the lateness of the Spring equinox, with further support from the frail condition of pigeons and lambs.

The Tosefta continues by describing those factors for which the year is or is not intercalated. First, the year is intercalated only by adding an additional Adar. Second, the year is intercalated by a full month, not less or more. Third, while it was best not to intercalate two years in a row, evidence is given that Akiva even intercalated three years in a row. Fourth, the Sh’mittah year (sabbatical year) is not intercalated nor the year following the Sh’mittah. Fifth, a year in which there is famine is not intercalated. Sixth, the year was not intercalated on the basis of ritual impurities among the people since the second Pesach was instituted for this contingency, though the Tosefta notes that R. Judah did intercalate the year because of uncleanness. This section is then concluded with the following;

They intercalate the year only when it needs it. They intercalate it because of roads, because of ovens, and because of the residents of the Exilic Communities, who have not been able to go forth from their homes. But they do not intercalate the year because of cold, snow, or the Exiles who already have made the ascent [for the pilgrimage]. But all of those factors do they treat as additional reason [for intercalating] the year. And if they intercalated the year [on these accounts], lo, it is deemed intercalated. (t.Sanhedrin 2.12)

Let us summarize, then, the view of the Mishnah and the additional information of the Tosefta:

1. Primary in the consideration of intercalating the year were these three things: a. if the barley was ripe and ready for reaping so that the sheaf could be waved b. if the fruit was mature and thus the first-fruits could be offered at Shavuot c. if the Spring equinox had occurred

2. The decision was made by a panel of judges consisting of three, or five if the three were divided, or seven if the five were divided.

3. Three regions were investigated to determine if the criteria were evident for intercalating the year: Judah, Trans-Jordon, and Galilee. Similar criteria in any two would suffice for the decision, though if the decision were made on the basis of only one region, the ruling of the judges was still considered valid.

4. The intercalation of the year added a full month, Adar II, of 30 days.

5. Additional factors that could “tip the scales” in favor of intercalating the year were: a. the roads (which would include bridges) were not yet repaired after the winter rains, which would have made the pilgrimage impossible, dangerous, or very difficult for the people. b. the clay ovens used for making the matzah were not yet dried out from the winter rains. c. the exiles had not been able to start out for their journey to Jerusalem, most likely because the winter rains had not yet ceased. However, if the exiles had already begun their journey, this would preclude intercalating the year (even if the weather turned bad), for if the year were to be intercalated after they had set out, they would make it to Jerusalem only to wait a full month before Nisan arrived. This would cause undue hardship for all.

6. The Sh’mittah (sabbatical) year was not intercalated nor the year following.

7. A year in which there was severe famine was not intercalated.

From these factors we may reach an obvious and necessary conclusion: one simply cannot expect to use astronomical means in an attempt to calculate which years in the pre-destruction era might “fit” various scenarios presented in the Gospels. For example, if one were to presume that the crucifixion of Yeshua occurred on the 15th of Nisan, and that this day was a Friday, it is futile to calculate in which years this might have taken place by reference to new moons. Since there is no record which years were intercalated and which were not, and since intercalation took place on other than astronomical grounds, one cannot be sure whether intercalation occurred in a year that “fits” on purely astrological grounds.25

The Mishnah also includes information concerning how the new moon was determined, both for the first month (Nisan) and the seventh month (Tishri). Mishnah Rosh HaShannah 1.1ff goes into detail about how the witnesses who had sighted the moon were examined to determine if they were trustworthy. This detailed examination would seem to indicate that false witnesses had been encountered, perhaps in order to coerce the Sanhedrin into proclaiming a sectarian calendar. Indeed, the Talmud contains just such a report about the attempt of the Boethusians to mislead the Sanhedrin.26

The method by which the sighted new moon was announced throughout the country was this: originally flares were waved from hilltop to hilltop, but apparently the Samaritans, using the same sign, caused confusion, and so messengers were sent instead.27

In terms of how a month is reckoned, only full days are used. Thus some months have 29 days (called “defective” חָסֵר, chaser) while others have 30 (called “full” מָלֵא, malei). The months Nisan, Sivan, Av, Tishri, Shevat and (in a leap year) Adar 1 are always full. Iyyar, Tammuz, Elul, Tevet, and Adar (Adar II in a leap year) are always defective. Cheshvan and Kislev vary. In this way the common year contains 353, 354, or 355 days and the leap year 383, 384, or 385 days. It can be seen that the postponement of the first day of the year may be necessary depending upon when the molad28 falls, for if not, a year would contain one too many days.29 The Mishnah contains a notice that there must be no less than four, and no more than eight full months in a year.30

After the destruction of the Temple and the expulsion of the Jewish community from Jerusalem, the Sanhedrin functioned less and less in the determination of the calendar, and a more rigid and fixed calendar needed to be put into place. But in the time of the 2nd Temple it seems clear that the declaration of the calendar, and particularly its intercalation, was in the hands of the Sanhedrin. And how the sectarian groups received the rulings of the Sanhedrin is not recorded. It is possible that in some cases sectarian groups intercalated their calendar differently than the Sanhedrin, but there is no extant data to explain to us how they might have done this, or how they would have existed within the larger society with a calendar that was in every way at odds with the ruling authority.

If we may trust the notice of b.Sanhedrin 11b, then before 70 CE the first and seventh month were declared by the Sanhedrin based upon the sighting of the moon, and the adjustments necessary for the calendar’s intercalation on the basis of other factors as noted above.

What Calendar did Yeshua & Disciples Follow?

An obvious question to be asked by those of us who are followers of Yeshua is: “what calendar did He use?” Obviously, the Gospels are the only valid source of information by which this question could be answered, and when we investigate the Gospels, we find a consistent pattern: Whenever the Gospels portray Yeshua and His disciples attending a festival in Jerusalem, they do so when multitudes of other people are likewise celebrating the festival there. This is conclusive evidence that Yeshua followed the majority calendar, for He attends the festivals at the same time as did the majority of the Jewish population.

The history of Yeshua’s observance of the yearly festivals in the Synoptic Gospels is limited to His celebration of Pesach. None of the other festivals are ever mentioned in the Synoptics.

Luke records that when Yeshua was 12 years old, He and His parents went up to Jerusalem for Pesach:

Now His parents went to Jerusalem every year at the Feast of the Passover. And when He became twelve, they went up there according to the custom of the Feast….

Καὶ ἐπορεύοντο οἱ γονεῖς αὐτοῦ κατ᾿ ἔτος εἰς Ἰερουσαλὴµ τῇ ἑορτῇ τοῦ πάσχα. Καὶ ὅτε ἐγένετο ἐτῶν δώδεκα, ἀναβαινόντων αὐτῶν κατὰ τὸ ἔθος τῆς ἑορτῆς (Lk 2:41–42)

Significant for our study is the notice given here by Luke that they “went up there according to the custom of the Feast.” The Greek κατὰ τὸ ἔθος τῆς ἑορτῆς (“according to the custom of the Feast”) clearly suggests that they followed the normal or majority calendar as to when Pesach was to be observed. The Greek word ἔθος (ethos) in this context means “long-established usage or practice common to a group.”31

Likewise, the concerted voice of the Synoptics in re-telling the final Pesach observance by Yeshua and His disciples picture them in Jerusalem at the same time as the “chief priests and elders of people” are celebrating the festival and when crowds of people are also congregated in Jerusalem for Pesach or Chag HaMatzot (Matt 26:3; 27:20; Mark 14:1; Luke 20:19; 22:2; John 19:6). Moreover, John tells us that the Jewish leaders petitioned Pilate that the legs of the crucified ones might be broken because it was the “preparation day” and they wanted the bodies taken down from the crosses before the Shabbat. Further, John tells us that the Shabbat which was coming was a “high day,” apparently meaning it was the weekly Shabbat within the seven days of Chag haMatzot (Feast of Unleavened Bread).

Then the Jews, because it was the day of preparation, so that the bodies would not remain on the cross on the Sabbath (for that Sabbath was a high day34), asked Pilate that their legs might be broken, and that they might be taken away. (Jn 19:31)

Clearly, the celebration of Pesach in which Yeshua and His disciples participated, and at which time He was crucified, was the very time that the majority of the people were celebrating the festival. Thus, Yeshua and His disciples were following the majority calendar which was determined by the Sanhedrin. They were not following the sectarian calendar of Qumran, for had they done so, they (like the Qumran sect) would not have been in Jerusalem. Further, there is no indication whatsoever that the Sadducees had a different yearly calendar than did the Pharisees, even if they did differ from the Pharisees on how to count the omer.

Only in John do we read about Yeshua’s celebration of other festivals. For instance, in John 10:22f, we see Yeshua in Jerusalem at the Feast of Dedication, i.e., Hanukkah. But John also tells us about the time Yeshua was in Jerusalem for the Festival of Sukkot:

Now the feast of the Jews, the Feast of Sukkot, was near. Therefore His brothers said to Him, “Leave here and go into Judea, so that Your disciples also may see Your works which You are doing.…Yeshua said to them, “My time is not yet here, but your time is always opportune. The world cannot hate you, but it hates Me because I testify of it, that its deeds are evil. Go up to the feast yourselves; I do not go up to this feast because My time has not yet fully come.” Having said these things to them, He stayed in Galilee. But when His brothers had gone up to the feast, then He Himself also went up, not publicly, but as if, in secret.…But when it was now the midst of the feast Yeshua went up into the temple, and began to teach.…Now on the last day, the great day of the feast, Yeshua stood and cried out, saying, “If anyone is thirsty, let him come to Me and drink….” (Jn 7:2ff)

From this notice in John, we may learn several things. First, Yeshua’s brothers, who at that time did not believe that He was the promised Messiah (cf. Jn 7:5) and thus were not numbered among His disciples, were celebrating Sukkot in Jerusalem along with the crowds of people (cf. vv. 12, 20, 31–32, 43, 49), meaning this was the celebration of Sukkot as reckoned by the majority calendar, i.e., the calendar as prescribed by the Sanhedrin. That Yeshua joined the festival and remained the entire eight days tells us that He too celebrated Sukkot according to the majority calendar as regulated and declared by the Sanhedrin.

Second, why would John refer to the Festival of Sukkot as “the feast of the Jews” (Jn 7:232 5)? Surely everyone knew that a festival called חַג הַסֻּכּוֹת, chag hasukkot, was a festival which the Jewish community observed! Beasley-Murray interprets the phrase “of the Jews” to mean “of the Jewish authorities,”33 which would suggest a meaning such as “the feast as lead by the Jewish authorities.” Carson interprets the meaning similarly:

Both in 5:18 and here [7:1], ‘the Jews’ refers to ‘the Judeans’ or, more precisely, the Jewish authorities in Judea.34

It therefore seems most likely that John’s use of the phrase “a feast of the Jews” should be understood to mean that the festivals so described were those that took place at the time set by the Judean authorities, i.e., the Sanhedrin.

Since the Gospel accounts make it clear that Yeshua celebrates His final Pesach in Jerusalem at the same time that the chief priests and elders were celebrating the festival (cf. Matt 26:1–5; Mk 14:1-2) as well as when the Passover lambs were being sacrificed in the Temple (Mk 14:12; Lk 22:7), we should understand that the calendar declarations of the Sanhedrin were followed both by Yeshua and His disciples. Likewise, it is inconceivable that Paul would declare himself a Pharisee (Acts 23:6) and adopt a non-Pharisaic calendar. After all, one of the primary issues separating the sects of the 1st Century was the calendar.


Here, then, we see an important precedent modeled by our Savior: He recognized that the calendar was regulated by the established authorities of the community, not by individuals sighting the new moon or the ripened barley, nor by observation of other astronomical phenomenon. While our Lord surely did not consider the Great Sanhedrin of His day to be accurate in all of their halachic rulings, nevertheless, in matters relating to calendrical reckonings, it is clear that He followed the calendar proclaimed by them. Further, even though there were alternate calendars being observed by sectarian groups in His day (such as the Qumran sect), neither He nor His disciples observed these calendars. Rather, they accepted the majority calendar, celebrating the festivals with the majority of the Jewish community. Given this reality, we should follow the example of our Master and His disciples and do the same.

1 I recognize the pitfalls in the indiscriminate use of the later rabbinic literature as though it actually offers a history of the pre-destruction era. Since, however, the rabbinic literature is, in many cases, the only literary source we have which offers explanations of calendrical issues, I am using it in hopes that it may offer us at least some insights into what might have been the calendar issues in the pre-destruction era. In doing so, I have sought to find references to authorities who lived in the pre-destruction era and who were recognized as established authorities in calendar matters.
2 1Kings 6:1, 37.
3 1Kings 6:38.
4 1Kings 8:2.
5 Ex 13:4; 23:15; 34:18; Deut 16:1.
6 Ezra 6:15; Esth 3:7,13; 8:12; 9:1,15,17,19,21.
7 Neh 2:1; Esth 3:7.
8 Zech 1:7.
9 Zech 7:1.
10 Neh 6:15.
11 Esth 2:16.
12 Esth 8:9.
13 Note the remarks of James C. Vanderkam, Calendars in the Dead Sea Scrolls (Routledge, 1998), p. 35.
14 Uwe Glessmer, “Calendars in the Qumran Scrolls” in The Dead Sea Scrolls After Fifty Years: A Comprehensive Assessment 2 vols, Flint and Vanderkam, eds. (Brill, 1999), 2:231.
15 Ibid., 233.
16 Cf. Gen 29:14; Num 9:22; 11:20; 1Kings 5:7; Is 66:23.
17 Cf. Ex 2:2; Deut 21:13; 1Kings 6:3f; 8:2; Zech 11:8; Job 3:6; 7:3; 29:2; 39:2.
18 For a good explanation of the methods of intercalation, see the article “Calendar” in the Encyclopedia Judaica, 5:43ff.
19 m.Rosh HaShannah 1:1ff
20 The idea that the “new moon” is in fact the full moon, which some base upon Psalm 81:3[4], is a misreading of the text and the poetic parallelism. First, some authorities (both ancient and modern) take the word rendered “full moon” in this text (כסה) as from the root כסס, “to count out” and thus translate “appointed” (KJV, “Blow up the trumpet in the new moon, in the time appointed, on our solemn feast day.”) Others take the word in question (כסה) to be equal to כסא and render it “full moon.” Still others take the word as it appears (כסה) and give it the normal meaning of “covered,” thus understanding it to refer to the moon when it is covered, i.e., not seen. Keil and Delitzsch think the text is referring to the festival of Passover, and that the blowing of the shofar is at the beginning of this month, while the festival itself is celebrated at the full moon, on the 14th-15th. Though this goes contrary to the normal interpretation of the text (which easily is seen to fit the festival of Yom Teruah or Rosh HaShannah), it certainly is a possible interpretation. Either way, however, this text does not teach that the month begins with the full moon. Taking the text as it stands, the “hidden” or “covered” moon is what is in mind.
21 The hour is divided into 1,080 parts (called חַלַקַים, chalakim) each of which is 3.33 seconds long. Thus, the final 44 minutes, 3.33 seconds of a day ארע noted as 739 chalakim in the rabbinic writings.
22 This is almost certainly Shimon b. Gamliel II, who lived in the early half of the 2nd Century CE.
23 t.Sanhedrin 2.2.
24 b.Sanhedrin 11b.
25 Beckwith works with all of the various criteria and offers numbers of options, but shows that these are, in fact, only options. One cannot be sure. See his Calendar and Chronology, Jewish and Christian (Brill, 2001), pp. 282–96. He shows here that in some instances, it appears that the new year (i.e., Nisan) was announced before the Spring equinox occurred, though this may have been in the case where the equinox would have occurred within sixteen days of the announcement, cf. t.Sanhedrin 2.7.
26 b.Rosh HaShannah 22b.
27 m.Rosh HaShannah 2:3
28 The Hebrew word מוֹלָד means “birth-time,” and was used to describe the exact time when the new moon (either actually sighted or mathematically calculated) appeared.
29 There were, of course, three other reasons for postponing the beginning of the year. For an explanation of these, see Encylopedia Judaica 5:44.
30 m.Arachin 2:2.
31 So BDAG, “ἔθος”.
32 Note that John also describes other Festivals by the phrase “a feast of the Jews.” Jn 5:1 (no specific festival is given; most feel it was either Pesach or Sukkot; 6:4 (Passover); 11:55 (Passover).
33 Beasley-Murray, John in Word Bible Commentary, vol. 36 (Word, 2006), p. 105.
34 D. A. Carson, John in PNTC (Eerdmans, 1991), p. 305.

Tim Hegg

President / Instructor

Tim graduated from Cedarville University in 1973 with a Bachelor’s Degree in Music and Bible, with a minor in Philosophy. He entered Northwest Baptist Seminary (Tacoma, WA) in 1973, completing his M.Div. (summa cum laude) in 1976. He completed his Th.M. (summa cum laude) in 1978, also from NWBS. His Master’s Thesis was titled: “The Abrahamic Covenant and the Covenant of Grant in the Ancient Near East”. Tim taught Biblical Hebrew and Hebrew Exegesis for three years as an adjunct faculty member at Corban University School of Ministry when the school was located in Tacoma. Corban University School of Ministry is now in Salem, OR. Tim is a member of the Evangelical Theological Society and the Society of Biblical Literature, and has contributed papers at the annual meetings of both societies. Since 1990, Tim has served as one of the Overseers at Beit Hallel in Tacoma, WA. He and his wife, Paulette, have four children, nine grandchildren, and three great-grandchildren.