A 3,500-year continuous lunisolar calendar. The religious year begins with Nisan in remembrance of the Exodus from Egypt; the civil year begins with Tishrei in remembrance of Creation. The shift from observation to calculation in 358 CE; every month begins with the new crescent, every seventh day with rest, every seventh year with the rest of the land, every fiftieth year with a full reset — a mathematical map of sacred time.
The Hebrew calendar is the oldest calendar system of the ancient world still in living use. While Mesopotamia's cuneiform tablets, Egypt's stone walls, and the Greek parapegma sit in museums, the Hebrew calendar rhythms the daily lives of roughly 15 million people worldwide. Shabbat still begins on Friday evening, Pesach is still celebrated on the 15th of Nisan, Yom Kippur is still the longest fast on the 10th of Tishrei. An ancient calendar, a modern life.
Moreover, this calendar fuses three distinct strata of time into a single system: the Moon (each month begins with the new crescent, 29 or 30 days), the Sun (Pesach must always fall in spring each year), and the Week (every seventh day is Shabbat). Unlike Egypt's strict solar reckoning, Babylon's pure lunisolar system, or Islam's purely lunar one, it harmonises three astronomical cycles within a seven-tiered mathematics. This is the most complex calendrical engineering of the ancient world.
But the matter is not mathematics alone. The Hebrew calendar is an expression of a theology of sacred time. Rest on the seventh day (Shabbat), rest of the land on the seventh year (Shemitah), and after seven times seven years, the Yovel (a full reset in the fiftieth year — manumission of slaves and restoration of lands to their original owners). The cosmic repetition of the number seven across seven months, seven days, seven years, and seven-times-seven years; the mathematical rhythm of the cosmos bound to socio-economic justice. No other calendar system in the ancient world has established so comprehensive a sacred-time ethic.
This tool unfolds that system in sequence. For the Hebrew year you select, the 12 months (13 in leap years) are laid out; for each month you see its Babylonian-derived name, its older Canaanite/biblical name (Aviv, Ziv, Eitanim, Bul), its season, agricultural cycle, attendant festivals and significant days. The Three Pilgrimage Festivals (Pesach, Shavuot, Sukkot) and Yamim Noraim (Rosh Hashanah, Yom Kippur, and the Days of Repentance between them) are treated in their own sections. The Shemitah and Yovel cycles are explained; Hillel II's reform (the shift from observation to calculation, 358 CE) and the Metonic mathematics behind it are demonstrated. The Gezer Calendar (10th century BCE, the oldest known Hebrew inscription) is presented as archaeological evidence of the agricultural-calendrical weave.
There is no outward grandeur of Babylon, no monumentality of Egypt, no philosophy of Greece, no law of Rome here. Instead, there is living time: a cosmological system that pauses every seven days, returns to its land every seven years, and resets every fifty years. The Hebrew calendar is the most enduring fragment of the ancient world — and it is still speaking.
Conversion between the Hebrew year (Anno Mundi, AM) and the Gregorian year. Calculated according to the arithmetic system fixed by Hillel II in 358 CE. AM 1, in Jewish tradition, is the year of Creation (3761 BCE).
A distinctive feature of the Hebrew calendar: two separate beginnings within the same year. The Mishnah (ca. 200 CE) in fact recognises four new years; two of them are central.
The Hebrew calendar is built on twelve months; in leap years, Adar I is inserted before Adar. The names were adopted during the Babylonian exile of the 6th century BCE; before that, months were called by number alone (only four had older Canaanite names: Aviv, Ziv, Eitanim, Bul). Click on a card to see etymology, season, and festivals.
The three pilgrimage festivals commanded by the Torah (Shemot 23:14-17; Devarim 16:16): three times a year "all males shall appear before the Lord," ascending to Jerusalem. Each is at once a historical memorial of deliverance and a seasonal turning point in the harvest.
The oldest and most central festival of the Hebrew calendar. Commanded directly in the Book of Exodus (Shemot 12), it commemorates the deliverance of the Jewish people from slavery in Egypt. Its historical dimension is preserved in the haggadah (the text read at the Seder table); in every generation, each person must see themselves as if they personally had gone out of Egypt that night ("bekhol dor vador hayyav adam lirot et atzmo ke'ilu hu yatza miMitsrayim").
At its agricultural root lies the beginning of the barley harvest; the phrase Hag haAviv ("Festival of New Growth") captures precisely this season. On 16 Nisan, the Omer (a measure of new barley) was offered at the Temple; from this point, the 49-day count to Shavuot began. The anchoring of the Exodus in the calendar is structural: Pesach must fall in spring; the Metonic 19-year cycle and the addition of Adar I exist for precisely this reason.
Fifty days after Pesach; the day after the 49th day of the Omer. The name itself comes from this count: "Weeks" (shavuot), that is, 7x7+1. The agricultural dimension is paramount: the beginning of the wheat harvest, the day on which the first fruits (bikkurim) were brought to the Temple (Devarim 26:1-11). The farmer would come with his basket and recite the formula summarising the story of deliverance.
The tradition that the Torah was given at Mount Sinai on this day consolidated during the rabbinic period (ca. 2nd-3rd century CE). This rabbinic development added a new theological stratum to Shavuot: harvest = Torah; first fruits = Revelation. This duality remains alive today. The all-night Torah study (Tikkun Leil Shavuot) is a symbolic re-enactment of the preparation for Mount Sinai.
The third of the Three Pilgrimage Festivals and the most joyful (Devarim 16:14-15: "You shall rejoice in your festival"). Coming five days after Yom Kippur, it bears a structural contrast as a festival of joy arriving immediately after purification. Its agricultural root: asif ("ingathering") — the height of the grape, olive, date and fig harvest. Its historical root: remembrance of the people who lived in tents in the wilderness for forty years after the Exodus.
For seven days one lives in the sukkah (a temporary booth); its roof (schach) must be of natural material and the sky must be visible through it. The arba minim ("four species" — lulav-palm branch, etrog-citron, hadas-myrtle, arava-willow) are waved; an orientation to God from the four directions, from heaven and earth. On the eighth day comes Shemini Atzeret (a separate festival); followed by Simchat Torah, marking the completion of the Torah-reading cycle (the same day in Israel, the following day in the diaspora).
The ten-day period between Rosh Hashanah and Yom Kippur (Aseret Yemei Teshuvah, "Ten Days of Repentance"). The most theologically intense interval of the Jewish liturgical year: judgment, repentance, atonement. A sacred span extending from 1 Tishrei to 10 Tishrei.
One of the four new years defined by the Mishnah (Tishrei 1), and the point at which the AM year number advances. The anniversary of Creation ("hayom harat olam"; "today the world was conceived"). In its theology as Day of Judgment, God judges all humanity — but this judgment is not immediately final; ten days for repentance are granted until Yom Kippur.
The central ritual is the shofar (ram's horn). One hundred blasts in all, in various sequences (tekiah, shevarim, teruah). The shofar calls forth three theological meanings: a summons to judgment, a remembrance of Mount Sinai, and a call to the messianic age. The Tashlich ritual involves going to flowing water to cast away one's sins symbolically. Foods include: apple with honey (for a sweet year), pomegranate (for merits as numerous as the 613 mitzvot), and the head of a fish (to be the head, not the tail).
The holiest day of the Jewish calendar. The Torah commands "you shall afflict your souls" (Vayikra 16:29-31; 23:27-32); the rabbinic tradition interprets this through five classical prohibitions: eating and drinking, bathing, anointing with oil, leather shoes, and marital relations. A full 25-hour fast, from the appearance of stars in the evening until stars on the following evening.
Five prayer services are held in the synagogue: Maariv (Kol Nidre), Shacharit, Musaf, Mincha, and Ne'ilah. The Kol Nidre evening prayer is one of annulment of vows; historically, an annulment before God of vows extorted under coercion (especially during the Marrano era). The Ne'ilah (closing service) is the climax: the final opportunity before the gates of heaven shut. The Vidui (confession of sins) is recited communally; its alphabetical ordering and impersonal form lend the congregation a sense of collective belonging.
Yom Kippur and Tisha b'Av are the only two full-day fasts of the Jewish calendar, yet their meanings stand in opposition: Tisha b'Av is a fast of catastrophe and mourning, Yom Kippur a fast of purification and hope. This opposition is central to the theological architecture of the calendar.
The heartbeat of the Hebrew calendar. Every seventh day, a 25-hour pause from the appearance of evening stars to the next. A reflection of the seventh day of Creation; the cosmological rhythm upon which the entire structure of the calendar rests.
Shabbat is the only unit of the calendar with no astronomical referent. Neither moon, nor sun, nor stars; it derives solely from the rhythm of the Creation account. In Bereshit 2:2-3, on the seventh day God "finished His work and rested." In the theology of the Hebrew calendar, this is the Archimedean point of the cosmos: the structure of the week could be nothing but seven days, because seven is the number of rest.
The weekly cycle was unknown in the ancient Near East. The 30-day months of Babylon were divided into three ten-day segments; the Egyptian decans were ten-day. The seven-day week is an Israelite invention and spread from there into the Greco-Roman world and thence into the modern world. Although the seven planets of Babylon (Sun, Moon, and the five classical planets) may have influenced the number, the Torah's framing is not astronomical but ethical-theological: the seventh day is the day of rest, not the day of any moon-god or stellar calculation.
The halakhic tradition (Mishnah Shabbat 7:2) defines 39 principal categories of forbidden work (melachot); these are derived from the labours performed in constructing the Tabernacle (Mishkan). The prohibition is against creative work, against interference with the natural order; on Shabbat, the human being forgets they are master of the world. In modern practice, this means refraining from kindling fire (including electricity), from writing, from commerce, from riding animals, from financial transactions.
The sociological force of Shabbat: for 3,500 years, a people that has paused every seventh day has preserved its own calendrical identity in resistance to the rhythms of capitalist production, the obligations of monarchy, and the pressures of war. In Heschel's phrase, Shabbat is "a palace in time": a sacred space created not in space but in time.
Shabbat is family time: Friday evening kabbalat Shabbat (welcoming the Sabbath), the kindling of candles, kiddush (blessing over wine), challah (braided bread) blessing, and three family meals. Intimate time between spouses is commanded as oneg Shabbat (the delight of Shabbat). On Saturday afternoon, se'udat shlishit (the third meal); in the evening, the closing ritual of havdalah (separation): a blessing over wine, spices, and a braided candle, returning to the world of the weekday.
The weekly rhythm of Shabbat expands, at the scale of the year, into Shemitah (the seventh year), and at the scale of the generation, into Yovel (the fiftieth year — after seven-times-seven years). The most comprehensive sacred-time ethic of the ancient world; it periodically resets the land, the economy, and the social order.
The seven-year cycle commanded in Vayikra 25:1-7 and Devarim 15. Every seventh year, the land observes a Shabbat: sowing, harvesting, and pruning are forbidden. Whatever grows on its own is treated as ownerless and is open to all; the poor and the stranger may gather freely. Shemitah means "release": releasing the land, the produce, and possession.
Devarim 15:1-3 adds a further Shemitah rule: the remission of debts. Debts owed by one Jew to another are automatically cancelled at the end of the Shemitah year. This is a radical reset for a sustainable economy: a limit on the accumulation of debt, and a guarantee that the poor do not remain in debt from one generation to the next. Hillel the Elder (1st century BCE) developed the legal mechanism known as prozbul to make this rule practically workable; through assignment of debts to the court, debts could be exempted from Shemitah remission.
Today in Israel, Shemitah is still observed (most recently: 5782 / 2021-2022). For the modern Israeli farmer, two principal solutions exist: (1) heter mechira (the symbolic sale of the land to a non-Jew for the Shemitah year; contested by Orthodox circles); (2) otzar beit din (placing cultivation under the supervision of a rabbinical court). The religious care for the produce (kedushat shevi'it) is preserved.
The seventh year is the golden one: the land rests, debts are remitted, ownership is temporarily suspended.
Vayikra 25:8-13 commands: after seven Shemitah cycles (49 years), the fiftieth year is the Yovel. Yovel in fact means "ram's horn" (the same word appears in Joshua 6:4-5), because the Yovel year is proclaimed by the shofar on the morning of Yom Kippur: "Proclaim liberty throughout all the land" (Vayikra 25:10) — the verse inscribed on America's Liberty Bell.
Yovel has three principal effects: (1) The land rests (as in Shemitah; both the 49th and 50th years). (2) Slaves are freed: Hebrew slaves sold 50 years before regain their freedom and return to their families. (3) The land is returned: agricultural land sold 50 years before reverts to its original family ownership. This is a mechanism by which economic inequality is structurally reset; the concentration of land cannot be sustained from generation to generation.
The sociological radicalism of Yovel is striking: private property is not absolute; every family has its ancestral land granted by God; a sale operates like a temporary lease (limited to 50 years). This is a theory of property unparalleled in modern law. Vayikra 25:23: "The land shall not be sold in perpetuity, for the land is mine."
Historically, after the Babylonian exile (586 BCE), Yovel was no longer observed in practice. Talmudic debates concluded that Yovel applies only when all twelve tribes dwell in the Land of Israel (Arakhin 32b). Today in the State of Israel, Yovel is not observed; Shemitah is. Yet Yovel endures as an ethical model.
The mathematical heart of the Hebrew calendar. 19 solar years ~ 235 lunar months; this approximation is the ancient Near Eastern discovery that preserves the lunisolar balance. Adopted during the Babylonian exile, fixed by Hillel II's reform (358 CE).
The fundamental problem of a lunisolar calendar: 12 lunar months yield about 354 days; the solar year is 365.25 days. The approximately 11-day gap accumulates from year to year; in a decade, 110 days; in a generation, the seasons would invert. If Pesach must always fall in spring, then the calendar requires the periodic insertion of a month.
In the early 5th century BCE, Babylonian mathematicians discovered: 19 solar years ~ 235 lunar months. In this equation, when 7 intercalary months are added across a 19-year cycle (that is, 7 years out of 19 have 13 months), the moon and sun are brought into average agreement. The Greek astronomer Meton (432 BCE) introduced this cycle in Athens, and the Greeks named it the "Metonic cycle." But it was known to the Babylonians far earlier — by the early 5th century BCE (Parker and Dubberstein, Babylonian Chronology 626 B.C.-A.D. 75).
Hillel II's reform (358 CE) officially embedded this Metonic cycle within the Hebrew calendar. The leap years are: years 3, 6, 8, 11, 14, 17, and 19 of the 19-year cycle. In these years, Adar I (30 days) is inserted before Adar; Pesach remains on 15 Nisan, but Nisan itself is shifted back by a few weeks, falling in spring.
In a 19-year cycle: 12 regular years + 7 leap years. Total: 12 x 12 + 7 x 13 = 235 months. 235 x 29.5306 = 69,386.7 days ~ 19 x 365.2422 = 6,939.6 days. The discrepancy is only about 2 hours per 19 years; a one-day drift accumulates over approximately 220 years.
The reform carried out by Patriarch Hillel II in 358-359 CE: the shift of the Hebrew calendar from an observation-based system to a mathematical-calculated one. The most important calendar reform in Jewish history; the foundation of 1,600 years of continuous operation.
During the Second Temple and Talmudic periods, the Hebrew calendar relied on two principal mechanisms: (1) Rosh Chodesh (the start of a new month) was determined by witnesses; two trustworthy Jews would report to the Sanhedrin (the Jewish High Court) that they had seen the new crescent, the court would confirm, and the month would officially begin. (2) Ibbur (the intercalation of a leap month) depended on agricultural observation; if spring appeared late — if barley had not yet ripened, if lambs had not yet been born — the court would add a second Adar (Adar Sheni) after Adar.
This system drew its light each month from Jerusalem: the Sanhedrin's decisions were transmitted to the Babylonian-Persian diaspora through beacon-signals and messengers. But the Roman Empire suppressed Jewish autonomy during the 2nd-4th centuries CE: Constantius II (337-361) forbade the Sanhedrin from convening and from proclaiming new months. Festivals began to be observed on different days across the transcontinental diaspora.
Patriarch Hillel II, as head of the Sanhedrin, resolved to make public the "hidden science" of calendar calculation. The calendar would henceforth depend not on witnesses but on mathematics. Three principal decisions:
The Sanhedrin determined the new month from witness testimony; the message was disseminated by beacon and messenger.
The leap month (ibbur) was tied to agricultural observation; the ripening of barley and the birth of lambs were the criteria.
The new month is calculated from the molad (the mean conjunction); the molad interval = 29 days, 12 hours, 793 chalakim (1 chalak = 1/1080 of an hour).
Leap years are fixed at years 3, 6, 8, 11, 14, 17, and 19 of the 19-year Metonic cycle.
The molad constant (29 days, 12 hours, 793 chalakim ~ 29.530594 days) is remarkably accurate: it differs from the true mean synodic month (29.530588 days) by mere seconds. This precision likely derives from the lunar eclipse records of the 8th-5th centuries BCE (from Babylonian System B, ca. 300 BCE). Hipparchus and Ptolemy used the same value (Almagest, 2nd c. CE).
The reform was not completed in a single stroke. According to Hai Gaon (10th c.), what is attributable to Hillel himself is only the formalisation of the 19-year cycle; the further details (the lengths of months, the dehiyot or postponement rules) developed in subsequent centuries. According to Sacha Stern's work, the fixed calendar reached its final form only in 922-924 CE. But the underlying structure is attributed to Hillel II.
The meaning of the reform is cosmological: the Jewish calendar is no longer bound to the momentary decision of a political authority (the Sanhedrin); it is bound to a mathematical formula. This allowed every Jewish community in the diaspora to calculate its own calendar without waiting for Jerusalem's ruling. The victory of exile's calendar over empire.
10th century BCE, the Solomonic era. An 11 x 7 cm limestone tablet; the oldest known Hebrew (or paleo-Canaanite) inscription. An agricultural-calendrical text; archaeological evidence of Jewish calendar knowledge.
The Irish archaeologist R.A.S. Macalister discovered it in 1908 during excavations at Gezer (30 km west of Jerusalem). 11.1 cm tall, 7.3 cm wide; the size of a mobile phone. Written in the paleo-Hebrew / Early Canaanite alphabet; at the bottom corner of the tablet appears what is probably the name of the scribe, "Abiya." It is dated to the 10th century BCE (on palaeographic grounds); it may have been written between the time of King Solomon and the Egyptian pharaoh Shishak.
Today it is exhibited at the Istanbul Archaeology Museums, since the excavation took place on Ottoman territory. A replica is also held at the Israel Museum. The content: the twelve months of the agricultural calendar, but not by name — rather a list of activities.
The key word is yerah (𐤉𐤓𐤇), meaning "month" (both the moon-as-body and the calendar month). Yerahw is the dual ending, meaning "two months." A complete breakdown of the 12-month agricultural year, beginning from Tishrei and running through Elul.
This inscription documents three things: (1) The Israelites/Canaanites of 10th-century BCE Gezer were already using a 12-month calendar system; this is 400 years before the Babylonian exile, hence the system existed before the Babylonian names were adopted. (2) The cycle of agricultural activity is the concrete ground of the Jewish festivals: Pesach in Aviv (barley) because the barley harvest falls in this month; Shavuot 50 days later because the wheat harvest falls in that season; Sukkot in Tishrei because the ingathering is at its height. The festivals are embedded in the agricultural cycle. (3) This is one of the earliest known Hebrew inscriptions; it attests to the continuity of Jewish writing and calendar knowledge.
The theological essence of the Hebrew calendar: the conversion of time from mathematical structure into ethical effect. The most comprehensive system of sacred time in the ancient world.
The Hebrew calendar founds itself on the cyclical repetition of seven. Seven days make a week, the last of which is Shabbat. Seven weeks make the Omer (from Pesach to Shavuot, 7x7 = 49 days, followed by the 50th day, Shavuot). Seven months mark the passage from the religious to the civil year (7 months between Nisan and Tishrei). Seven years make the Shemitah cycle. Seven-times-seven years make the Yovel (49 years + the 50th year = a full reset).
This is a fractal cosmological architecture. At every scale the same sevenfold pattern repeats; day-week-month-year-generation. The microcosm (the week) is mirrored in the macrocosm (the generation); the same law operates at different time-scales. Unlike the Hindu Vedic yugas, this is not merely numerical but ethical-rhythmic. The number seven symbolises not nature but sanctity.
The Hebrew calendar has two faces: a memory that looks back and an anticipation that looks forward. Pesach remembers the Exodus from Egypt; Shavuot remembers the receiving of the Torah at Sinai; Sukkot remembers forty years in tents in the wilderness — these look back. Rosh Hashanah judges each year anew; Yom Kippur grants forgiveness each year anew; Shemitah restarts the economy every seven years; Yovel performs a full reset of fifty years — these look forward. It is at once archive and programme; a calendar that is both history and utopia.
Messianic expectation is added to this dual structure: "Le'shanah haba'ah biRushalayim" ("Next year in Jerusalem"), recited at the close of every Yom Kippur and at the end of every Pesach Seder; every festival opens onto a deliverance that has not yet occurred. No other calendar of the ancient world bears so explicit a future-orientation.
The experience of the Jewish diaspora transformed the nature of the calendar. The exiled Jew lived severed from land, kingdom, and Temple; what remained in hand was time. In Abraham Joshua Heschel's phrase, Judaism developed an "architecture of time": a people unable to build palaces in space built palaces in time. Every Shabbat is a palace; every festival a vaulted gateway; every Shemitah a courtyard. The calendar became the principal carrier of Jewish identity.
This is the form in which the ancient Near Eastern cosmology was internalised and ethicised by Judaism. The calendrical knowledge of Egypt, Babylon, and Mesopotamia was received (the Babylonian month-names, the Metonic cycle, the synodic-month constant) — but this knowledge was wrested from the hands of political authority and transferred into the mathematical possession of the people. Hillel II's reform is the final stage of that transition: faith is no longer placed in the emperor's decree but in the formula. The calendar is democratised.
The classical, academic, and technical literature on which this reconstruction relies. From the Torah and Talmud to modern mathematical scholarship.
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About the Hebrew calendar
The Hebrew calendar has multiple new years (rashei shanim), as enumerated in the Mishnah (Rosh Hashanah 1:1). Nisan, in early spring, is the religious or biblical new year - the first month of the liturgical cycle, beginning with Pesach - while Tishri, in early autumn, is the civil and agricultural new year, opening with Rosh Hashanah. The dual structure reflects two complementary cycles: Nisan begins the sacred history of the Exodus, while Tishri marks creation and judgement.
The Shalosh Regalim - Pesach, Shavuot, and Sukkot - are the three biblical pilgrimage festivals during which the Israelites were commanded to appear at the Temple in Jerusalem (Exodus 23:14-17, Deuteronomy 16:16). Pesach commemorates the Exodus in the spring, Shavuot celebrates the giving of the Torah and the wheat harvest fifty days later, and Sukkot marks the autumn ingathering and the dwelling in booths during the wilderness journey. Each festival has both a historical and an agricultural dimension that anchors the religious calendar to the land of Israel.
The Yamim Noraim - the "Days of Awe" - are the ten-day period from Rosh Hashanah (1 Tishri) to Yom Kippur (10 Tishri), considered the most solemn time of the Jewish year. Tradition holds that on Rosh Hashanah the Books of Life and Death are opened, and on Yom Kippur they are sealed; the intervening days are devoted to teshuvah (repentance), tefillah (prayer), and tzedakah (charity). The liturgy of this period, including the Avinu Malkenu, Untaneh Tokef, and Kol Nidre, structures both the religious calendar and the spiritual life of the community.
The Hebrew calendar is lunisolar, so a thirteenth month - Adar II (Adar Sheni) - is inserted seven times in every nineteen-year cycle (years 3, 6, 8, 11, 14, 17, and 19) to keep Pesach in the spring, as required by Deuteronomy 16:1. In an embolismic year, Adar I has thirty days and Adar II has twenty-nine; the festivals associated with Adar, including Purim and the yahrzeit of Moses (7 Adar), are observed in Adar II. This nineteen-year cycle is the same Metonic period used in Babylonian astronomy.
Traditionally in 359 CE, the patriarch Hillel II is credited with promulgating a fixed arithmetical calendar to replace the older system of monthly proclamation by witnesses before the Sanhedrin. Under Roman and Byzantine persecution, communication between the land of Israel and the diaspora had become unreliable, threatening uniform observance of the festivals. Hillel II's reform introduced the molad calculation (mean conjunction), the four dehiyyot (postponement rules), and the nineteen-year intercalation cycle, producing the predictable calendar still in use today.
Shemitah is the sabbatical year, every seventh year (Leviticus 25:1-7), in which agricultural fields lie fallow, debts are released, and the produce of the land is declared ownerless. Yovel, the Jubilee, falls every fiftieth year - after seven Shemitah cycles - and involves the additional remission of debts, the liberation of Hebrew slaves, and the return of ancestral land to its original family. While Yovel is no longer practised, Shemitah continues to be observed in modern Israel, with elaborate halakhic procedures regulating agriculture and commerce during that year.