The Modern Jewish Calendar
by Ernest L. Martin, Ph.D., 1976
The present calendar which governs the religious holydays of the Jewish people (and some Christian denominations) is NOT the calendar of the Bible. Though the features which govern it are wonderfully devised and represent a masterpiece of mathematical calculation, it is still different from the calendar which we find in the Bible. Indeed, it was not constructed until about 300 years after the time of Christ and it is certainly not the biblical calendar.
The first calendar indications of the Bible show that each of the months had 30 days. It is recorded in the book of Genesis that the period of Noah's Flood in its unabated state was from the 2nd month, 17th day (Gen. 7:11) until the 7th month, 17th day of the month (8:4). This span equals exactly five months and was 150 days in length (7:24 with 8:3). This indicates that each month had 30 days, and consequently 360 days was the length of the year. This agrees with the prophetic interpretation of the year as shown in Daniel 7:25 and 12:7. The book of Revelation also interpreted the length of the month and year in a similar fashion. Three and a half years represented 1260 days, or 42 months, or a time, times, and half a time (Rev. 12:6,14; 13:5). But since it is well known that in the time of Daniel and the Revelation the real length of the month was just over 29 1/2 days and the year just under 365 1/4 days, these periods must be looked on as ideal and symbolic, not actual ones. Of course, when God creates the new heavens and earth, He could bring the month and year lengths into these precise configurations, but as for now (and certainly since the time of King Hezekiah when the Sun went "back" ten degrees) we have our present month and year measurements in effect.
Our present Gregorian calendar relies strictly on the motions of the Sun and pays no attention to the Moon whatever. The biblical calendar, however, combines both Lunar and Solar motions in its scheme. All months begin with their respective new moons (Isa. 66:23). In fact, the word for "month" and "new moon" is the same in Hebrew.
All the ancient festival periods of Israel (other than the weekly Sabbaths) were determined by the days of the Moon (month) Yet the festivals were agricultural in design and were also required to be kept in their proper seasons as governed by the Sun (Exo. 13:10). The state of the crops near Jerusalem were important in the performance of the festival ceremonies (Lev. 23:9-21), and if the crops were not sufficiently mature, the ecclesiastical year would be postponed one month to accommodate this. While the Temple rituals were in operation, this seasonal feature always had to be taken into account. Thus, the motions of the Sun were acknowledged, by the priests in their determination of the calendar year. This was necessary so that the proper times for the celebrations of the rituals were not disturbed. This feature shows that the rituals governed the calendar, not vice versa. The calendar was part and parcel of the ritualistic system that God imposed upon ancient Israel. Those who presently insist on observing the biblical calendar of the Old Testament must recognize that they are perpetuating the use of the ritual system which Christ did away with long ago.
"In which were offered both gifts and sacrifices, that could not make him that did the service perfect, as pertaining to the conscience; which stood only in meats and drinks, and divers washings, and carnal ordinances, imposed on them until the time of reformation."
Why should Christians want to continue with ritualistic systems now made redundant in Christ? Of course, most don't realize this though it is nonetheless true.
The present Jewish calendar avoids the commandment to watch the state of the crops around Jerusalem for the determination of the year's beginning. It is an entirely calculated one without actual reference to the motions of the Sun or Moon. It has even introduced more ritualistic features not even suggested by the biblical legislation. For example, the present Jewish calendar prohibits the first day of each month from occurring on certain days of the week. It will not allow the first day of Tishri (the seventh day of the month the Day of Trumpets) to happen on a Sunday, Wednesday, or Friday. This new rule, which was devised after biblical times, prevents the weekly Sabbaths in the Autumn from occurring in tandem with annual holydays. This rule came into effect about the middle of the fourth century A.D. However, in the Mishnah, the earliest part of the Talmud which was composed about the beginning of the third century, the rule did not apply. Festival days could then occur next to the weekly Sabbath (Erubin 3:6). And though the modern Jewish calendar prohibits the Day of Trumpets (the civil New Year) from happening on a Sunday, this was not so in the time of Christ nor for two centuries after (Shabbath 19:5).
Also, the month of Elul (the sixth month) sometimes had 30 days ascribed to it in the time of Christ (if the Sanhedrin so decreed), yet the modern Jewish calendar never allows it to have more than 29 days (Danby, "The Mishnah," p. 125). One such day in error may not seem like too much, but coupled with the rule that three particular weekdays for the beginning of months are prohibited (as explained above), this could mean two or three days' divergence from the truth.
Besides this, if the new moon is calculated on the modern calendar to occur on or after the hour of noon, it is the next day that becomes the first of the month. But if this day is a prohibited day, the month is further postponed another day. Again, this rule was not in effect in Christ's day and it has nothing to do with the original biblical calendar.
The present Jewish calendar is ingeniously constructed and shows the brilliance of the scholars who devised it, but it must be recognized that it is NOT astronomically correct. The assumed length of the year is too long by six minutes, thirty nine and one third seconds. This may appear insignificant, but it is not. This discrepancy causes the whole Jewish calendar to creep forward on the true seasons one day in every two hundred and sixteen years. The Passover of the present calendar is already, in 1977, almost eight days ahead of the seasons as regulated by the Sun from its initiation in the fourth century A.D. If this process is allowed to continue, the Passover of the Jews (plus those of all our Christian friends who follow the same modern calendar) will be occurring in late Springtime and finally early Summer. This feature is in complete disharmony with the teachings of Scripture about the proper time for the celebration of Passover. However, if the simple observational rules which regulated the calendar in the time of our Lord were still in operation (instead of a calculated calendar which pays no attention to the actual positions of the Sun and Moon) such problems would never happen.
Would anyone think it proper to observe the Passover in Winter? If there is anything more plain about the calendar rules in the biblical period, it is that Passover must be a Springtime festival, not a Winter celebration. Indeed, Josephus, the Jewish historian who lived in the time of the apostles (who was a priest of the first rank) stated the rule that Passover had to be a Springtime feast (Antiquities, Bk. III, X, 5). And Philo Judaeus, an Alexandrian Jew who lived in the time of Christ and who was well acquainted with Jewish religious beliefs, said that Passover occurred after the Spring Equinox (Ten Festivals, Ch. XI). Other Jewish authorities also maintained the same fact as absolutely necessary to its proper observance. Anatolius called attention to this major rule which governed the calendar in the time of Christ. "This [truth] may be learned from what is said by Philo, Josephus, and Musaeus; and not only by them, but also by those yet more ancient, the two Agathobuli, sir named 'Masters,' and the famous Aristobolus [third century B.C.], who was chosen among the seventy in terpreters for the sacred and divine Hebrew Scriptures [the LXX] by Ptolemy Philadelphus and his father. . These writers, explaining questions in regard to the Exodus, say that all alike should sacrifice the passover offerings AFTER THE VERNAL EQUINOX in the middle of the first month" (Eusebius, "Church History" 32:18).
But strange as it may seem, the present Jewish calendar (which avoids the use of the actual positions of the Sun and Moon) was so devised that in its first hundred or so years of existence, it had Passover occurring a few times back in the Winter season even before the Spring Equinox. This shows that it was devised in fundamental error from its very beginning. Our Christian friends who insist in keeping Passover according to the present reckoning of the Jews are certainly NOT being guided by the calendar of Christ.
No matter how one looks at it, there are several differences between the modern Jewish calendar and the biblical one. For a fuller discussion on these matters write for our 50 page booklet titled Passover, Lord's Supper, Communion. A history of the major problems concerning the Jewish calendar are there given in detail
Ernest L. Martin
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