The concept of a calendar in biblical times is deeply rooted in the agricultural and religious life of the Israelites. The calendar was primarily lunar, with months beginning at the sighting of the new moon. This system is evident in various biblical texts and was essential for determining the timing of religious festivals and agricultural activities.

Lunar Calendar:
The Hebrew calendar was based on lunar months, each consisting of 29 or 30 days. This is reflected in the term "new moon," which is frequently mentioned in the Bible as a time of significance. For instance, in 1 Samuel 20:5, David says to Jonathan, "Behold, tomorrow is the New Moon, and I should not fail to sit with the king at the meal." The new moon marked the beginning of the month and was often a time for special sacrifices and feasts (Numbers 28:11-15).

Months and Seasons:
The Hebrew calendar consisted of twelve months, with an occasional thirteenth month added to align the lunar calendar with the solar year. The months were closely tied to the agricultural cycle, with names reflecting seasonal activities. For example, the month of Abib (later called Nisan) is associated with the barley harvest and the Passover festival (Exodus 13:4). The Bible often refers to months by their ordinal number, such as "the first month" or "the seventh month" (Leviticus 23:24).

Religious Festivals:
The calendar was crucial for determining the dates of the major Jewish festivals, which were divinely instituted and held great religious significance. The Passover, celebrated in the first month, commemorated the Israelites' deliverance from Egypt (Exodus 12:2-14). The Feast of Weeks, or Pentecost, occurred seven weeks after the Passover and marked the wheat harvest (Leviticus 23:15-21). The Feast of Tabernacles, in the seventh month, celebrated the end of the harvest and God's provision during the Israelites' wilderness wanderings (Leviticus 23:34-43).

Sabbath and Jubilee:
The concept of the Sabbath, a day of rest on the seventh day, is foundational in the biblical calendar (Exodus 20:8-11). Additionally, the calendar included sabbatical years, occurring every seventh year, during which the land was to lie fallow (Leviticus 25:4). The Year of Jubilee, every fiftieth year, was a time of liberation and restoration, when slaves were freed, and land was returned to its original owners (Leviticus 25:10).

Prophetic Significance:
The calendar also holds prophetic significance in the Bible. The seventy weeks prophecy in Daniel 9:24-27 is an example where specific time periods are used to convey future events. The precise timing of Jesus' crucifixion and resurrection is linked to the Passover and the Feast of Firstfruits, fulfilling Old Testament typology and prophecy (1 Corinthians 5:7, 15:20).

Conclusion:
The biblical calendar is a complex system that intertwines religious observance, agricultural cycles, and prophetic symbolism. It reflects the rhythm of life for the ancient Israelites and underscores the importance of time in God's redemptive plan.Genesis 1:14
And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:
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Deuteronomy 4:19
And lest you lift up your eyes to heaven, and when you see the sun, and the moon, and the stars, even all the host of heaven, should be driven to worship them, and serve them, which the LORD your God has divided to all nations under the whole heaven.
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2 Peter 3:10
But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up.
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1. (n.) An orderly arrangement of the division of time, adapted to the purposes of civil life, as years, months, weeks, and days; also, a register of the year with its divisions; an almanac.

2. (n.) A tabular statement of the dates of feasts, offices, saints' days, etc., esp. of those which are liable to change yearly according to the varying date of Easter.

3. (n.) An orderly list or enumeration of persons, things, or events; a schedule; as, a calendar of state papers; a calendar of bills presented in a legislative assembly; a calendar of causes arranged for trial in court; a calendar of a college or an academy.

4. (v. t.) To enter or write in a calendar; to register.

CALENDAR

kal'-en-dar (Latin calendarium, "an account book," from calendae, "day on which accounts were due"): The Hebrew or Jewish calendar had three stages of development: the preexilic, or Biblical; the postexilic, or Talmudic; and the post-Talmudic. The first rested on observation merely, the second on observation coupled with calculation, and the third on calculation only. In the first period the priests determined the beginning of each month by the appearance of the new moon and the recurrence of the prescribed feasts from the vernal and autumnal equinoxes. Thus, the month Abib ('abhibh), the first month of the year according to the Levitical law, in which the Passover was to be celebrated, was determined by observation (Exodus 12:2 Deuteronomy 16). After the exile more accurate methods of determining the months and seasons came into vogue, and calculation was employed to supplement and correct observations and the calendar was regulated according to the Babylonian system, as is evidenced by the names of the months which are derived from it. In later times the calendar was fixed by mathematical methods (see the article "Calendar" in the Jewish Encyclopedia). The difficulty of ascertaining the first day of the new moon by observation, in the early period, led to the celebration of two days, as seems to be indicated in 1 Samuel 20:27. We have only four names of months belonging to the pre-exilic period, and they are Phoenician. Of these Abib ('abhibh) was the first month, as already indicated, and it corresponded to Nis (nican) in the later calendar. It was the month in which the Exodus occurred and the month of the Passover (Exodus 13:4; Exodus 23:15; Exodus 34:18 Deuteronomy 16:1).

The 2nd month of this calendar was Ziv (ziw) (1 Kings 6:1, 37); Ethanim ('ethanim) was the 7th (1 Kings 8:2), corresponding to Tishri of the later calendar, and Bul (bul) the 8th, corresponded to Marchesvan (marcheshwan) (1 Kings 6:38). There were course other month names in this old calendar, but they have not come down to us. These names refer to the aspects of the seasons: thus Abib ('abhibh) means grain in the ear, just ripening (Leviticus 2:14 Exodus 9:31); Ziv (ziw) refers to the beauty and splendor of the flowers in the spring; Ethanim ('ethanim) means perennial, probably referring to living fountains; and Bul (bul) means rain or showers, being the month when the rainy season commenced. The full calendar of months used in the postexilic period is given in a table accompanying this article. The names given in the table are not all found in the Bible, as the months are usually referred to by number, but we find Nican in Nehemiah 2:1 and Esther 3:7; Siwan in Esther 8:9; Tammuz in Ezekiel 8:4, although the term as here used refers to a Phoenician god after whom the month was named; 'Elul occurs in Nehemiah 6:15; Kiclew (the American Standard Revised Version "chislev") in Nehemiah 1:1 and Zechariah 7:1; Tebheth in Esther 2:16; ShebhaT in Zechariah 1:7 and 'Adhar in Ezra 6:15 and several times in Est. These months were lunar and began with the new moon, but their position in regard to the seasons varied somewhat because of the intercalary month about every three years.

The year (shanah) originally began in the autumn, as appears from Exodus 23:16 and Exodus 34:22, where it is stated that the feast of Ingathering should be at the end of the year; the Sabbatic year began, also, in the 7th month of the calendar year (Leviticus 25:8-10), indicating that this had been the beginning of the year. This seems to have been a reckoning for civil purposes, while the year beginning with Nican was for ritual and sacred purposes. This resulted from the fact that the great feast of the Passover occurred in this month and the other feasts were regulated by this, as we see from such passages as Exodus 23:14-16 and Deuteronomy 16:1-17. Josephus (Ant., I, iii, 3) says: "Moses appointed that Nican, which is the same with Xanthicus, should be the first month of their festivals, because he brought them out of Egypt in that month; so that this month began the year as to all solemnities they observed to the honor of God, although he preserved the original order of the months as to selling and buying and other ordinary affairs." A similar custom is still followed in Turkey, where the Mohammedan year is observed for feasts, the pilgrimage to Mecca and other sacred purposes, while the civil year begins in March O. S.

The year was composed of 12 or 13 months according as to whether it was ordinary or leap year. Intercalation is not mentioned in Scripture, but it was employed to make the lunar correspond approximately to the solar year, a month being added whenever the discrepancy of the seasons rendered it necessary. This was regulated by the priests, who had to see that the feasts were duly observed at the proper season. The intercalary month was added after the month of 'Adhar and was called the second 'Adhar (sheni, wa-'adhar, "and Adar"), and, as already indicated, was added about once in 3 years. More exactly, 4 years out of every 11 were leap years of 13 months (Jewish Encyclopedia, article "Calendar"), this being derived from the Babylonian calendar. If, on the 16th of the month Nican, the sun had not reached the vernal equinox, that month was declared to be the second 'Adhar and the following one Nican. This method, of course, was not exact and about the 4th century of our era the mathematical method was adopted. The number of days in each month was fixed, seven having 30 days, and the rest 29. When the intercalary month was added, the first 'Adhar had 30 and the second 29 days.

H. Porter

388. Ethanim -- (month of) "steady flowings," the seventh month in ...
... (month of) "steady flowings," the seventh month in the Jewish calendar. Transliteration:
Ethanim Phonetic Spelling: (ay-thaw-neem') Short Definition: Ethanim. ...
/hebrew/388.htm - 6k

3691. Kislev -- the ninth month of the Jewish calendar
... 3690, 3691. Kislev. 3692 . the ninth month of the Jewish calendar. Transliteration:
Kislev Phonetic Spelling: (kis-lave') Short Definition: Chislev. ...
/hebrew/3691.htm - 6k

24. abib -- fresh, young ears, also Canaanite name for the first ...
... fresh, young ears, also Canaanite name for the first month of the Jewish calendar.
Transliteration: abib Phonetic Spelling: (aw-beeb') Short Definition: Abib. ...
/hebrew/24.htm - 6k

7627. Shebat -- eleventh month in the Jewish calendar
... 7626, 7627. Shebat. 7628 . eleventh month in the Jewish calendar. Transliteration:
Shebat Phonetic Spelling: (sheb-awt') Short Definition: Shebat. ...
/hebrew/7627.htm - 6k

945. Bul -- the eighth month of the Jewish calendar
... 944, 945. Bul. 946 . the eighth month of the Jewish calendar. Transliteration:
Bul Phonetic Spelling: (bool) Short Definition: Bul. ...
/hebrew/945.htm - 6k

143. Adar -- the twelfth month in the Jewish calendar
... 142, 143. Adar. 144 . the twelfth month in the Jewish calendar. Transliteration:
Adar Phonetic Spelling: (ad-awr') Short Definition: Adar. ...
/hebrew/143.htm - 6k

2099. Ziv -- the second month of the Jewish calendar
... 2098, 2099. Ziv. 2100 . the second month of the Jewish calendar.
Transliteration: Ziv Phonetic Spelling: (zeev') Short Definition: Ziv. ...
/hebrew/2099.htm - 6k

144. Adar -- the twelfth month in the Jewish calendar
... 143, 144. Adar. 145 . the twelfth month in the Jewish calendar. Transliteration:
Adar Phonetic Spelling: (ad-awr') Short Definition: Adar. ...
/hebrew/144.htm - 6k

Syriac Calendar.
... Memoirs of Edessa. And Other Ancient Syriac Documents. [Translated by the Rev.
BP Pratten, BA] Syriac Calendar. A Note by the Translator ...
//christianbookshelf.org/unknown/the decretals/syriac calendar.htm

The Moon's Age Set Forth in the Julian Calendar. ...
... Section XIII. The moon's age set forth in the Julian Calendar.? The moon's
age set forth in the Julian Calendar. January, on the ...
/.../the paschal canon of anatolius of alexandria/section xiii the moons age.htm

Some Carriages of the Adversaries of God's Truth with Me at the ...
... month (1662) following; and when they came, because I had a desire to come before
the judge, I desired my jailor to put my name into the calendar among the ...
/.../grace abounding to the chief of sinners/some carriages of the adversaries.htm

Subject Index
... Burial of the Dead, [2387]According to the Directory, [2388]Changes to Service.
Calendar, [2389]Calendar, [2390]Calendar. Calendar or Pie, [2391]Calendar or Pie ...
/.../luckock/studies in the book of common prayer/subject index.htm

"Christ Also Waits. "
... The only calendar we men have is a calendar of dates, fitted to the movements
of the sun and moon. God has a calendar, too, but ...
/.../gordon/quiet talks with world winners/christ also waits.htm

Noble Company.
... of our Lord, which we are specially bound to keep in our minds, with reverence and
godly fear, on All Saints' Day, lest by arranging our calendar of saints ...
/.../kingsley/westminster sermons/sermon xxii noble company.htm

The Man Sent Ahead.
... We moderns, who do everything by the calendar, have been puzzled in the attempt
to piece together these events into an exact calendar arrangement. ...
//christianbookshelf.org/gordon/quiet talks about jesus/the man sent ahead.htm

Whosoever Shall Presume to Set Aside the Decree of the Holy and ...
... This was owing to the adoption of the Gregorian calendar, and this misfortune while
that calendar is followed it is almost impossible to prevent. [168]. ...
/.../schaff/the seven ecumenical councils/canon i whosoever shall presume.htm

Introduction
... He is allowed in the Primer Calendar by unauthorised Marshall, 1535; out in Crumwell
and Hilsey's, 1539; out by the authorised Primer of King and Clergy, 1545 ...
//christianbookshelf.org/marson/hugh bishop of lincoln/introduction.htm

B. --The Festal Letters, and their Index,
... He gives, in a paragraph corresponding to each Easter in the episcopate of Athanasius,
a summary of the calendar data for the year, a notice of the most ...
/.../select works and letters or athanasius/b the festal letters and their.htm

Calendar
... 3. (n.) An orderly list or enumeration of persons, things, or events; a schedule;
as, a calendar of state papers; a calendar of bills presented in a ...
/c/calendar.htm - 13k

Tammuz (1 Occurrence)
... In the Chaldean calendar there was a month set apart in honour of this god, the
month of June to July, the beginning of the summer solstice. ...
/t/tammuz.htm - 10k

Adonijah (28 Occurrences)
... forty years" (2 Samuel 15:7). The natural meaning is not forty years after the
last-mentioned preceding date, but at the close of the fortieth calendar year of ...
/a/adonijah.htm - 22k

Easter (1 Occurrence)
... The rule was finally adopted, in the 7th century, to celebrate Easter on the Sunday
following the 14th day of the calendar moon which comes on, or after, the ...
/e/easter.htm - 12k

Year (4027 Occurrences)
... The Jews reckoned the year in two ways, (1) according to a sacred calendar, in which
the year began about the time of the vernal equinox, with the month Abib ...
/y/year.htm - 26k

Month (197 Occurrences)
... "The Hebrews and Phoenicians had no word for month save 'moon,' and only saved their
calendar from becoming vague like that of ... See CALENDAR; TIME; ASTRONOMY. ...
/m/month.htm - 44k

Trumpets (52 Occurrences)
... 2. Significance: The significance of the feast lay in the fact that it marked
the beginning of the new year according to the older calendar. ...
/t/trumpets.htm - 32k

Library
... 3. Religious Texts: A knowledge of astronomy was needed for the regulation of the
calendar, and the calendar was the special care of the priests, as the ...
/l/library.htm - 16k

Battle (282 Occurrences)
... can the sun have been rising, and the moon setting, since this would imply that
the time of year was either about October 30 of our present calendar, or about ...
/b/battle.htm - 55k

Feast (209 Occurrences)
... 2. Significance: The significance of the feast lay in the fact that it marked
the beginning of the new year according to the older calendar. ...
/f/feast.htm - 47k

What is the structure of the Jewish calendar? | GotQuestions.org

What is the Christian calendar? | GotQuestions.org

What is an advent calendar? How does an advent calendar relate to Christmas? | GotQuestions.org

Calendar: Dictionary and Thesaurus | Clyx.com

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