Exodus 12 · Leviticus 23, 25 · Esther · Nehemiah · Featured Study
The Hebrew Calendar
Israel counted its months by the moon, its years by two different starting lines, and kept the whole system anchored to spring with an extra month added when the arithmetic demanded it. This page walks the mechanism plainly: the new moon, the names Scripture actually gives the months, and the numbers behind the sabbatical and jubilee years, checked by hand.
I. Lehrberger u. Comp., Rödelheim, Hebrew calendar for the year 1840/41, 1840. CC BY-SA 4.0.
Summary
Israel's month began at the new moon, announced by trumpet, and its year opened in two places at once: the religious year at Nisan in spring, and an older civil year that turned in the fall. A thirteenth month, added seven years in nineteen, kept the lunar calendar from drifting out of spring, and the same numbering (seven sevens, then the fiftieth year) governs both the weekly sabbath and Israel's sabbatical and jubilee years.
- Only four early Hebrew month names survive in Scripture (Abib, Ziv, Ethanim, Bul); seven of the twelve names in common use today came home from Babylon and appear in Esther, Nehemiah, Ezra, and Zechariah.
- Five familiar month names (Iyar, Tammuz, Av, Tishri, Cheshvan) never appear anywhere in the Hebrew Bible; they surface only in post-biblical Jewish sources.
- Exodus 12:2 commands Nisan as the year's first month; Exodus 23:16 and 34:22 still call the autumn harvest feast the 'end of the year,' the trace of an older fall reckoning.
- Twelve lunar months run about 11 days short of the sun's year; post-biblical Jewish practice added a leap month, Adar II, in 7 of every 19 years to keep Passover in spring.
- Leviticus 25:8 counts seven sabbaths of years, 7 x 7 = 49, then hallows the fiftieth as the jubilee, an arithmetic question two public-domain commentators address directly.
The Lunar Month
the moon sets the calendar, and the trumpet announces it
1 SAMUEL 20:5 (BSB)
“Look, tomorrow is the New Moon, and I am supposed to dine with the king. Instead, let me go and hide in the field until the third evening from now.”
PSALM 81:3 (BSB)
“Sound the ram’s horn at the New Moon, and at the full moon on the day of our Feast.”
David expects a royal feast the next day for no reason beyond the new moon itself; Jonathan needs no further explanation. The Hebrew word for month, chodesh, is the same word used for the new moon: the month simply is the moon’s own cycle, counted.
“Blow up the trumpet in the new moon. Announce the sacred month, the beginning of months, when the Lord brought his people out of the house of bondage. Clear and shrill let the summons be which calls all Israel to adore the Redeeming Lord. In the time appointed, on our solemn feast day. Obedience is to direct our worship, not whim and sentiment: God's appointment gives a solemnity to rites and times which no ceremonial pomp or hierarchical ordinance could confer.”
Charles Spurgeon · The Treasury of David, Vol. 4, 1874Particular (Reformed) Baptist
Psa 81:3
- ~29.5 daysone lunar month
- 12 monthsthe ordinary year
- ~354 daystwelve lunar months, summed
- ~11 days shortof the sun's ~365-day year
What Scripture Calls the Months
two layers of names, and five names the Bible never uses
The early Hebrew names
Four names. Three of them name a month in Solomon’s own Temple-building record in 1 Kings, and Abib is cited from Exodus.
The Babylonian names, brought home from Exile
Seven names, every occurrence in a post-exilic book.
The five names Scripture never usesIyar, Tammuz, Av, Tishri, Cheshvan
Five month names in common Jewish use today do not appear anywhere in the Hebrew Bible: Iyar (2nd month), Tammuz (4th), Av (5th), Tishri(7th, the month Scripture itself only ever calls Ethanim or “the seventh month”), and Cheshvan(8th, Scripture’s Bul). These surface first in post-biblical Jewish sources, the Mishnah and later, not in the canon. The grid below still uses the modern names, honestly marked, so a reader can navigate the calendar in the terms living Jewish practice actually uses.
The words underneath
chodesh: month
Hebrew · H2320Strong's entry: the new moon; by implication, a month
The Hebrew word for both 'month' and 'new moon': the calendar's basic unit and its own announced beginning are one word.
284 times in the Old Testament · chodesh, in full →
yobel: jubilee/horn
Hebrew · H3104Strong's entry: the blast of a horn (from its continuous sound); specifically, the signal of the silver trumpets; hence, the instrument itself and the festival thus introduced
The word behind 'jubilee,' literally the blast of a ram's horn: the trumpet that opens the fiftieth year gives the year its own name.
27 times in the Old Testament · yobel, in full →
Two Years, One Calendar
the religious year opens in spring; an older civil year turned in the fall
“This month is the beginning of months for you; it shall be the first month of your year.” Exodus 12:2
Spoken the same month as the Exodus itself, this verse fixes Nisan (Abib) as month one of the religious year. Deuteronomy 16:1 repeats the command: “Observe the month of Abib and celebrate the Passover to the LORD your God.”
“this month shall be unto you the beginning of months--the first not only in order but in estimation. It had formerly been the seventh according to the reckoning of the civil year, which began in September, and continued unchanged, but it was thenceforth to stand first in the national religious year which began in March, April.”
Jamieson, Fausset & Brown · Commentary Critical and Explanatory on the Whole Bible, 1871Reformed
Exo 12:2
Scripture leaves its own trace of that older reckoning. Twice the Torah sets the autumn harvest feast, Tabernacles, at the close of the year:
EXODUS 23:16 (BSB)
“You are also to keep the Feast of Harvest with the firstfruits of the produce from what you sow in the field. And keep the Feast of Ingathering at the end of the year, when you gather your produce from the field.”
EXODUS 34:22 (BSB)
“the Feast of Ingathering at the turn of the year.”
The Hebrew at 34:22 is tequfat hashanah, the turn of the year, which older English Bibles render as the year’s end. Either phrase only makes sense if a year was already being counted from a point that lands its own close in the fall. Jewish practice still keeps both reckonings side by side rather than resolving them into one: Rosh Hashanah, the new year most Jews mark today, falls on the first of Tishri, the seventh month by the religious count Exodus 12:2 commands. The Mishnah names the overlap directly, listing four separate new years for different purposes: months and festivals from Nisan, the tithing of cattle from Elul, and “the new year for years,” the agricultural and civil year, from Tishri (Rosh Hashanah 1:1). Named, dated, and placed: reception history, never MannaFest’s own confession.
The Extra Month
Adar II: post-biblical calendar mechanism, kept in seven years of nineteen
Twelve lunar months of about 29.5 days each run to roughly 354 days, about 11 days short of the sun’s own year of about 365 days. Left uncorrected, Nisan would drift earlier every year, and within a decade or two Passover would no longer fall in spring, breaking the very command that fixes it there (Deuteronomy 16:1, “Observe the month of Abib”).
Jewish practice, visible by the Second Temple period and later fixed into a calculated calendar credited to Hillel II in the fourth century AD, corrected the drift by adding a thirteenth month, Adar II (Adar Sheni), in seven of every nineteen years. The nineteen-year cycle works because nineteen solar years and 235 lunar months land within about half a day of each other, the same cycle used in other ancient calendars. This is a described mechanism of post-biblical Jewish practice, not a scriptural institution; Scripture commands that Passover be kept in the month of Abib, but nowhere legislates the intercalation method itself.
- 354 daystwelve lunar months, summed
- 365 daysone solar year, roughly
- 7 of 19 yearscarry the extra month
- 19 years ≈ 235 monthsthe cycle's own check
The Year at a Glance
twelve months, their season, and what falls on each
early name: Ziv (1 Kings 6:1)
Spring (Apr-May)
Summer (Jun-Jul)
Summer (Jul-Aug)
Late summer (Aug-Sep)
early name: Bul (1 Kings 6:38)
Autumn (Oct-Nov)
Winter (Dec-Jan)
Winter (Jan-Feb)
Adar II (Adar Sheni), a thirteenth month, is inserted after Shebat and before Nisan in seven of every nineteen years (see “The Extra Month” above). Post-biblical calendar practice, not a named Scripture month.
† Name not found anywhere in the Hebrew Bible; known only from post-biblical Jewish tradition.
The Sabbatical and Jubilee Cycles
Leviticus 25: the seventh year's rest, the fiftieth year's liberty, the arithmetic checked
“For six years you may sow your field... But in the seventh year there shall be a Sabbath of complete rest for the land, a Sabbath to the LORD.” Leviticus 25:3-4
Every seventh year the land itself rests: no sowing, no pruning, no organized harvest. What grows on its own feeds the household, the servants, and the hired hand alike (25:5-6).
“The institution of the sabbatical year was designed, 1. To shew what a plentiful land that was, into which God was bringing them, that so numerous a people could have rich maintenance out of the products of so small a country, without foreign trade, and yet could spare the increase of every seventh year.”
John Wesley · Explanatory Notes upon the Old Testament, 1765Evangelical
Exo 23:10
“And you shall count off seven Sabbaths of years, seven times seven years, so that the seven Sabbaths of years amount to forty-nine years.” Leviticus 25:8
Seven sabbaths of years: 7 × 7 = 49, stated in the text and checked. Two verses later the trumpet sounds on the Day of Atonement to open what the text calls the fiftieth year:
“So you are to consecrate the fiftieth year and proclaim liberty in the land for all its inhabitants.” Leviticus 25:10
The count (49 years holding seven sabbatical years, then a 50th jubilee) is real arithmetic the text itself states; whether the 50th year is a fresh year after the 49th, or an inclusive count that folds the end of one 49-year span into the start of the next, is a question the commentators work through directly rather than one this page settles for the reader.
“Thou shalt number seven Sabbaths of years - This seems to state that the jubilee was to be celebrated on the forty-ninth year; but in Lev 25:10 and Lev 25:11 it is said, Ye shall hallow the fiftieth year, and, A jubilee shall this fiftieth year be. Probably in this verse Moses either includes the preceding jubilee, and thus with the forty-ninth makes up the number fifty; or he speaks of proclaiming the jubilee on the forty-ninth, and celebrating it on the fiftieth year current.”
Adam Clarke · Commentary on the Bible, 1832Methodist
Lev 25:8
- 7 yearsone sabbatical cycle
- 7 x 7 = 49seven sabbaths of years
- 50th yearthe jubilee, hallowed
- Day of Atonementthe trumpet that opens it
The theology of the jubilee (liberty, the land’s return, the typology it carries) belongs to its own page. Jubilee: the theology of the fiftieth year → The weekly sabbath this whole numbering echoes is its own study too. Sabbath Rest →
The Voices
with the work named
The Treasury of David, Vol. 4 (1874) · public domain
Reads Psalm 81:3's trumpet at the new moon as obedience giving solemnity to worship: God's own appointed times, not human sentiment, set the calendar's rhythm.
Commentary Critical and Explanatory on the Whole Bible (1871) · public domain
States the two reckonings side by side at Exodus 12:2: the civil year beginning in September stood unchanged even as the new religious year, beginning in spring, was commanded first place.
Explanatory Notes upon the Old Testament (1765) · public domain
On Exodus 23:10, reads the sabbatical year's design as proof of the land's own richness: a nation that could rest its fields one year in seven and still be fed.
Commentary on the Bible (1832) · public domain
Works through Leviticus 25:8's own arithmetic tension directly: whether the jubilee lands on the counted forty-ninth year or the fiftieth, and how the text can be read either way.
Marcus Brown's own commentary leads above all; within a tier, all voices are equal.
Word studies
The Hebrew and Greek under this study, each word in its own room.
Keep studying
Read it1
On this page
Doctrines11
- The Hebrew Feasts: what happens on this calendar, and why
- Jubilee: the theology of the fiftieth year
- Sabbath Rest: the weekly rhythm this calendar's sabbatical year echoes
- The Feast of Tabernacles: the seventh month's own autumn feast
- Passover: the feast that fixes Nisan to spring
- The Day of Atonement: the day the jubilee trumpet sounds