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ad pp. 277-280

CALENDAR

A calendar is an orderly system of dividing time into years, months, weeks and days. Long before man’s creation God provided the basis for such measuring of time. Genesis 1:14, 15 tells us that one of the purposes of the “luminaries in the expanse of the heavens” is that they might serve for “seasons and for days and years.” The solar day, the solar year and the lunar month are thus natural divisions of time, governed respectively by the daily turning of the earth on its axis, by its annual orbit around the sun, and by the monthly phases of the moon in its relation to earth and sun. The division of time into weeks and the division of the day into hours, on the other hand, are arbitrary ones.

From the Bible record we know that from the first man Adam forward time has been measured in terms of years. So we read that Adam was “a hundred and thirty years” of age when he became father to Seth.—Gen. 5:3.

Monthly divisions also came into use. By the time of the Flood we find time divided into months of thirty days, since a period of five months is shown to equal 150 days. (Gen. 7:11, 24; 8:3, 4) The same record also indicates that Noah divided the year into twelve months.—See YEAR.

Seven-day periods are mentioned at this time and may even have been in regular use since early in human history. (Gen. 7:4, 10; 8:10, 12) There is, however, no evidence of a divinely required weekly sabbath observance by man until God’s positive instructions to Israel following their exodus from Egypt.—See WEEK.

Various calendar systems have been developed by men in the past and a number continue in use today. Early calendars were mainly lunar calendars, that is, the months of the year were counted by complete cycles of the moon, as, for example, from one new moon to the next new moon. On the average, such lunation takes 29 days, 12 hours, 44 minutes and 2.78 seconds. The months were usually counted as of either 29 or 30 days, but in the Bible record the term “month” generally means 30 days.—Compare Deuteronomy 21:13; 34:8; also Revelation 11:2, 3.

A year of twelve lunar months falls nearly eleven days short of a solar year of 365 1⁄4 days. Since the solar year determines the return of the seasons, there was need to adjust the calendar to this solar year, and this resulted in what are called “lunisolar” or “bound solar” years; that is, years in which the months were lunar but the years were solar. This was done by the addition of a number of days each year or of an additional month during certain years to compensate for the shortness of the twelve lunar months.

HEBREW CALENDAR

The Israelites used such a lunisolar or bound solar year calendar. This is evident from the fact that Jehovah God established the beginning of their sacred year with the month Abib in the spring and specified the celebration of certain festivals on fixed dates, festivals that were related to harvest seasons. For these dates to have coincided with the particular harvests, there had to be a calendar arrangement that would synchronize with the seasons by compensating for the difference between the lunar and solar years.—Ex. 12:1-14; 23:15, 16; Lev. 23:4-16.

The Bible does not indicate what method was originally used to determine when additional days or an additional or intercalary month should be inserted. It is logical, however, that either the vernal or the autumnal equinox served as a guide to indicate when the seasons were falling behind sufficiently to require calendar adjustment. (See YEAR.) Though not specifically mentioned in the Bible, a thirteenth month that was added by the Israelites to accomplish this adjustment was called, in post-captivity times, Veadar, or Adar Sheni (II).

In written history we do not find record of a definitely fixed or standardized form of Jewish calendar until the fourth century of our Common Era (about 359 C.E.), when Hillel II specified that the leap years of thirteen months should be the 3d, 6th, 8th, 11th, 14th, 17th and 19th of each nineteen years. Such a nineteen-year cycle is commonly called the Metonic cycle, after the Greek mathematician Meton (of the fifth century B.C.E.), although there is also evidence that such a cycle was perfected before him by the Babylonians. (See Babylonian Chronology by Parker and Dubberstein [1956 ed.], pp. 1, 3, 6.) This cycle takes into account that every nineteen years the new and the full moons fall again on the same days of the solar year.

The Jewish months ran from new moon to new moon. (Isa. 66:23) Thus, one Hebrew word, hhoʹdhesh, rendered “month,” comes from a root meaning “new,” while the other principal word for month, yeʹrahh, means “lunation.” In later periods, fire signals were used or messengers were dispatched to advise the people of the new month’s beginning.

In the Bible the individual months are usually designated simply by numbering according to their position in the year, from the first through to the twelfth. (Josh. 4:19; Num. 9:11; 2 Chron. 15:10; Jer. 52:6; Num. 33:38; Ezek. 8:1; Lev. 16:29; 1 Ki. 12:32; Ezra 10:9; 2 Ki. 25:1; Deut. 1:3; Jer. 52:31) Only four months are named prior to the exile in Babylon, namely, Abib, the first month (Ex. 13:4), Ziv, the second (1 Ki. 6:37), Ethanim, the seventh (1 Ki. 8:2), and Bul, the eighth (1 Ki. 6:38). The meanings of these names are strictly seasonal, thus giving additional proof of a lunisolar year.—See the individual months by name.

In postexilic times the names of the months used in Babylon were employed by the Israelites, and seven of these are mentioned: Nisan, the first month, replacing Abib (Esther 3:7), Sivan, the third month (Esther 8:9), Elul, the sixth (Neh. 6:15), Chislev, the ninth (Zech. 7:1), Tebeth, the tenth (Esther 2:16), Shebat, the eleventh (Zech. 1:7), and Adar, the twelfth (Ezra 6:15).

The postexilic names of the remaining five months appear in the Jewish Talmud and other works. They are Iyyar, the second month; Tammuz, the fourth; Ab, the fifth; Tishri, the seventh; and the eighth month was called Heshvan. The thirteenth month, which was intercalated periodically, was named Veadar, that is, the additional Adar, or Adar Sheni, the second Adar.

Eventually the length of most of the months was fixed as having a specific number of days. Abib, Sivan, Ab, Ethanim (Tishri) and Shebat regularly had thirty days each; Ziv (Iyyar), Tammuz, Elul and Tebeth regularly had twenty-nine days each. Bul (Heshvan), Chislev and Adar, however, could have either twenty-nine or thirty days. The variations in these latter months served to make necessary adjustments with the lunar calendar, but also were used to prevent certain festivals from occurring on days viewed as “prohibited” by later Jewish religious leaders.

Whereas the sacred year began in the spring with the month Abib (or Nisan) by God’s decree at the time of the exodus (Ex. 12:2; 13:4), the Bible record indicates that prior to this the Jews had counted the year as running from fall to fall. God gave recognition to this arrangement so that, in effect, there was a dual system of a sacred and a secular or agricultural calendar used by his people. (Ex. 23:16; 34:22; Lev. 23:34; Deut. 16:13) In postexilic times, Tishri 1, in the last half of the year, marked the beginning of the secular year, and the Jewish New Year, or Rosh Hashanah (Hebrew, “head of the year”) is still celebrated on that date.

In 1908 the only approximation of an ancient written Hebrew calendar was found at the site of Gezer, and it is believed to be from the tenth century B.C.E. It is an agricultural calendar and describes agricultural activity beginning with the autumn. In brief, it describes two months each of storage, sowing and spring growth, followed by one month each of pulling flax, barley harvest and a general harvest, then two months of pruning the vines and, finally, one month of summer fruit.—Lev. 26:5.

The chart set out following this article shows the months in their relation to both the sacred and secular calendars and also their approximate correspondence to the months of our present calendar.

The frequent references in the Gospel accounts and the book of Acts to the various festival seasons show that the Jewish calendar continued to be observed by the Jews during the time of Jesus and the apostles. These festival seasons serve as a guide to measuring the relative time of the Biblical events of that day.—Matt. 26:2; Mark 14:1; Luke 22:1; John 2:13, 23; 5:1; 6:4; 7:2, 37; 10:22; 11:55; Acts 2:1; 12:3, 4; 20:6, 16; 27:9.

It should be noted that Christians, under the new covenant, are not governed by any sacred or religious calendar specifying certain holy days or festivals, a point that is clearly stated by the apostle Paul at Galatians 4:9-11 and Colossians 2:16, 17. The one event that they are required to observe annually is the Lord’s evening meal, at Passover time and so governed by the lunar calendar.—Matt. 26:2, 26-29; 1 Cor. 11:23-26; see LORD’S EVENING MEAL.

JULIAN AND GREGORIAN

In the year 46 B.C.E., the 708th year from the traditional date of the founding of the city of Rome, Julius Caesar issued a decree changing the Roman calendar from a lunar to a solar year. This Julian calendar, based on the calculations of the Greek astronomer Sosigenes, had twelve months of arbitrary length and a regular year of 365 days beginning on January 1. It also brought in the use of leap years by the addition of an extra day every four years, to compensate for the extra fraction of a day in the length of the tropical year, which has a little less than 365 1⁄4 days.

The Julian calendar year was actually a little more than eleven minutes and fourteen seconds longer than the true solar year. Thus, by the sixteenth century a discrepancy of ten full days had accumulated. In 1582 C.E., Pope Gregory XIII introduced a slight revision of the Julian calendar, whereby the leap years every four years were retained but with the exception that only those century years with a number divisible by 400 were to be counted as leap years. By papal bull on March 1, 1582, ten days were to be omitted in that year, so that the day after October 4 became October 15. This Gregorian calendar is now in general use in most parts of the world. It is the basis for the historical dates used throughout this publication.

OTHER CALENDARS

In a number of countries today the Muslim people continue to use a religious calendar based solely on the lunar cycles and with no intercalary month to adjust the year to the true solar year. This results in a steady retrogression of all the seasons during a cycle of about every thirty-two and a half years.

In the western hemisphere an ancient calendar was developed centuries before our Common Era and used by both the Mayan and Aztec Indians of Mexico and Central America. It was an astronomical calendar and, as regards the length of the solar year, was slightly more accurate than the present Gregorian calendar.

Whereas Christians today customarily use the calendar in effect in their particular land, they are aware that the God of eternity, Jehovah, has his own calendar of events not governed by human systems of reckoning. As his prophet Daniel wrote: “He is changing times and seasons, removing kings and setting up kings, giving wisdom to the wise ones and knowledge to those knowing discernment. He is revealing the deep things and the concealed things, knowing what is in the darkness; and with him the light does dwell.” (Dan. 2:21, 22) So, in his position as Universal Sovereign he stands far above our spinning Earth, with its day and night, its lunar cycles and its solar year. However, in his Word, the Bible, he does helpfully relate his actions and purposes to such measurements of time, thereby allowing his creatures on earth to learn where they stand in relation to God’s grand calendar of events.—See CHRONOLOGY.

[Chart on pages 278-279]

THE CALENDAR MONTHS OF THE ISRAELITES

POSITION OF MONTH

Sacred: 1st

Secular: 7th

NAME: Abib or Nisan

FIXED DAYS (359 C.E.): 30

CORRESPONDENCE TO ENGLISH CALENDAR: March-April

FESTIVALS AND CELEBRATIONS

Days: 14

Occasion: Passover

Days: 15-21

Occasion: Unfermented cakes

Days: 16

Occasion: Offering of firstfruits

WEATHER: Later or spring rains begin and snows from Lebanon

Mountains melt, bringing Jordan River to flood stage.

CROPS, ETC.: Harvests of barley, flax in some sections. Wheat becomes ripe in Jordan valley. Carob trees bearing pods. Flocks now going out to fields.

POSITION OF MONTH

Sacred: 2nd

Secular: 8th

NAME: Ziv or Iyyar

FIXED DAYS (359 C.E.): 29

CORRESPONDENCE TO ENGLISH CALENDAR: April-May

FESTIVALS AND CELEBRATIONS

Days: 14

Occasion: Passover for those unable to keep regular one

WEATHER: Dry season now extends till about October; generally cloudless skies.

CROPS, ETC.: Wheat harvest in lower areas; barley harvest general. Grape vines flowering. Flowers abundant in uplands. Apricots ripening.

POSITION OF MONTH

Sacred: 3rd

Secular: 9th

NAME: Sivan

FIXED DAYS (359 C.E.): 30

CORRESPONDENCE TO ENGLISH CALENDAR: May-June

FESTIVALS AND CELEBRATIONS

Days: 6

Occasion: Festival of weeks (Pentecost)

WEATHER: Summer heat approaching. Air very clear. Occasional sirocco winds.

CROPS, ETC.: Wheat harvest in uplands. Early figs, almonds ripening. Honey gathered in Jordan valley. Apples on seacoast. Oleanders blossoming.

POSITION OF MONTH

Sacred: 4th

Secular: 10th

NAME: Tammuz

FIXED DAYS (359 C.E.): 29

CORRESPONDENCE TO ENGLISH CALENDAR: June-July

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER: Heat increases. Heavy dews form at night in some sections.

CROPS, ETC.: First ripe grapes. Vegetation and springs generally drying up.

POSITION OF MONTH

Sacred: 5th

Secular: 11th

NAME: Ab

FIXED DAYS (359 C.E.): 30

CORRESPONDENCE TO ENGLISH CALENDAR: July-August

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER: Heat reaching maximum.

CROPS, ETC.: Grape harvest begins.

POSITION OF MONTH

Sacred: 6th

Secular: 12th

NAME: Elul

FIXED DAYS (359 C.E.): 29

CORRESPONDENCE TO ENGLISH CALENDAR: August-September

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER: Heat still strong.

CROPS, ETC.: Vintage general. Dates ripe. Cotton and pomegranates ripening. Summer figs gathered.

POSITION OF MONTH

Sacred: 7th

Secular: 1st

NAME: Ethanim or Tishri

FIXED DAYS (359 C.E.): 30

CORRESPONDENCE TO ENGLISH CALENDAR: September-October

FESTIVALS AND CELEBRATIONS

Days: 1

Occasion: Trumpet blast

Days: 10

Occasion: Day of atonement

Days: 15-21

Occasion: Festival of booths or ingathering

Days: 22

Occasion: Solemn assembly

WEATHER: Summer ending. Beginning of transition to winter or rainy season. Early rains begin.

CROPS, ETC.: Harvest generally complete. Plowing begins.

POSITION OF MONTH

Sacred: 8th

Secular: 2nd

NAME: Bul or Heshvan, Marheshvan

FIXED DAYS (359 C.E.): 29 or 30

CORRESPONDENCE TO ENGLISH CALENDAR: October-November

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER: Generally rainy.

CROPS, ETC.: Sowing of wheat and barley. Shepherds bring flocks back in from fields for winter. Olive harvest.

POSITION OF MONTH

Sacred: 9th

Secular: 3rd

NAME: Chislev

FIXED DAYS (359 C.E.): 29 or 30

CORRESPONDENCE TO ENGLISH CALENDAR: November-December

FESTIVALS AND CELEBRATIONS

Days: 25

Occasion: Festival of dedication

WEATHER: Rainfall increases. In highlands nights frosty. Some snow on mountaintops.

CROPS, ETC.: Grass developing.

POSITION OF MONTH

Sacred: 10th

Secular: 4th

NAME: Tebeth

FIXED DAYS (359 C.E.): 29

CORRESPONDENCE TO ENGLISH CALENDAR: December-January

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER: Cold reaches maximum. Rainfall heavy, some hail, and in higher altitudes occasional snow.

CROPS, ETC.: In lowlands pastures green; grain developing. Many wild flowers.

POSITION OF MONTH

Sacred: 11th

Secular: 5th

NAME: Shebat

FIXED DAYS (359 C.E.): 30

CORRESPONDENCE TO ENGLISH CALENDAR: January-February

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER: Cold weather diminishing. Still rainy.

CROPS, ETC.: Almond trees blossom. Oranges ripen. Fig trees beginning to bud.

POSITION OF MONTH

Sacred: 12th

Secular: 6th

NAME: Adar

FIXED DAYS (359 C.E.): 29; 30 in leap year

CORRESPONDENCE TO ENGLISH CALENDAR: February-March

FESTIVALS AND CELEBRATIONS

Days: 14,15

Occasion: Purim

WEATHER: Frequent thunder and hail.

CROPS, ETC.: Carob trees in blossom. Barley ripening in Jordan valley. Citrus fruit harvest.

POSITION OF MONTH

Sacred/Secular: Intercalary

NAME: Veadar or Second Adar

FIXED DAYS (359 C.E.): 29

CORRESPONDENCE TO ENGLISH CALENDAR: Added after Adar

FESTIVALS AND CELEBRATIONS

Days:

Occasion:

WEATHER:

CROPS, ETC.:

[Picture on page 279]

The Gezer calendar

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