Table of contents of the website
Most Western calendars are solar, with 365 days (Wikipedia Gregorian Calendar), while others use the lunar calendar (Wikipedia Lunar Calendars). The lunar year has between 354 and 355 days. There is therefore a difference of approximately 11 days between the solar calendar (365 days) and the lunar calendar (354 days). Lunar months have approximately 29.5 days. The Hebrew calendar alternates between a 30-day month, followed by a 29-day month, and so on. However, the Hebrew calendar also takes into account the 365-day solar cycle, making it a « lunisolar » calendar (Wikipedia Hebrew Calendar) (Hebrew Calendar – Chiourim).
The key points to know about the biblical calendar, which is similar to the Hebrew calendar, are as follows:
The months of the Hebrew and Biblical lunisolar calendar:
First month: Nisan or Abib (in the Bible) (March-April) (30 days)
Second month: Iyyar or Ziv (in the Bible) (April-May) (29 days)
Third month: Sivan (May-June) (30 days)
Fourth month: Tammuz (June-July) (29 days)
Fifth month: Ab (July-August) (30 days)
Sixth month: Eloul (August-September) (29 days)
Seventh month: Tishri or Ethanim (in the Bible) (September-October) (30 days)
Eighth month: Hesvan or Bul (in the Bible) (October-November) (29 or 30 days)
Ninth month: Chislev (November-December) (29 or 30 days)
Tenth month: Tebeth (December-January) (29 days)
Eleventh month: Shebat (January-February) (30 days)
Twelfth month: Adar (February-March) (29 or 30 days)
Thirteenth month: Adar II or Veadar (29 days)
In the Hebrew lunisolar calendar, an intercalary month is regularly added to compensate for the 11-day difference between the lunar year (354 days) and the solar year (365 days). In this case, this year exceptionally has 13 months; it is a « lunisolar » year. Currently, the adjustment system used by the Hebrew calendar is made according to a Metonic cycle, which is a series of 7 adjustments over a period of 19 years (7 lunisolar years of 13 months), in order to synchronize the lunar years of 354 days, with the solar year of 365 days, over a period of 19 years. The thirteenth month is added in the 3rd year, the 6th year, the 8th year, the 11th year, the 14th year, the 17th year and the 19th year.
In the Bible, days begin in the evening, after sunset. For example, in Genesis 1:5, regarding the symbolic first day of creation, it is written: « And there was evening and there was morning, a first day ».
Months begin at the « new moon » (Psalm 81:3). They have either 30 or 29 days. However, at this stage of the study, there is a significant difficulty regarding the biblical definition of the new moon.
Normally the new moon « is the lunar phase during which the Moon, during its synodic revolution which lasts approximately 29.53 days, is between the Earth and the Sun » (Wikipedia New Moon). This is the astronomical new moon.
Others think that this is the first crescent of the moon , it is the religious new moon, the option chosen by the current Jewish calendar (See the link to the Hebrew calendar – Chiourim).
However, the Bible, based on Psalms 81:3, seems to designate the new moon as the opposite of the full moon, that is, when it is completely invisible (the astronomical new moon) (without the appearance of the first crescent).
In Psalm 81 it is written: « Blow the horn on the new moon, On the full moon, for the day of our festival » (Psalm 81:3). According to the context of this statement, it refers to the blowing of the trumpet on Ethanim (Tishri), 1, the new moon (the seventh month of the year) (Numbers 29:1) and the full moon on 15 Ethanim (Tishri) (Exodus 23:16).
The « day of our festival », seems to poetically indicate according to the context of Psalm 81, the Festival of Booths, being a time of great rejoicing (Psalm 81:1,2): « You should celebrate the Festival of Booths for seven days when you make an ingathering from your threshing floor and from your press for oil and wine. Rejoice during your festival, you and your son, your daughter, your male slave, your female slave, the Levite, the foreign resident, the fatherless child, and the widow, who are inside your cities. Seven days you will celebrate the festival to Jehovah your God in the place that Jehovah chooses, for Jehovah your God will bless all your produce and all that you do, and you will become nothing but joyful » (Deuteronomy 16:13-15).
To know which new moon it is on a biblical point of view, it is enough to consider that the first observable full moon (and even the astronomical full moon) corresponds to the 15th of the lunar month. Then, we must go back 15 days to see, on a lunar astronomical table, which new moon it is (astronomical or religious). (See photo of the lunar table for the month of March 2025).
Based on the lunar astronomical table for March 2025 (see above), the astronomical full moon is March 14. Considering that this day corresponds to the 15th of the lunar month, according to the Bible (Psalms 81:3), we just have to go back 15 days from that day (the 15th), and we arrive at February 28, 2025 (which does not appear in the photo above) which corresponds to the astronomical new moon (a completely invisible moon).
As a second example, in April 2025, the observable full moons are on April 11 and 12, while the astronomical full moon is on April 13. Based on the observable full moons (on the 11th and 12th), we are in the phase of complete invisibility of the moon (on March 28 and 29, 2025), and based on the astronomical full moon, it is the day after the astronomical new moon (March 30, 2025).
As a third example, in May 2025, the observable full moon is on May 11, 2025, while the astronomical full moon is on May 12, 2025. Going back 15 days, we arrive either at the astronomical new moon on May 27, 2025, or in its phase of complete invisibility, on May 28, 2025. Thus, simply by these three examples, we understand that on the biblical basis, the new moon corresponds to the astronomical (non-religious) one.
Is it so important?
« Therefore, do not let anyone judge you about what you eat and drink or about the observance of a festival or of the new moon or of a sabbath » (Colossians 2:16). This text could imply that the issue related to the new moon is not so important to a Christian. According to the context of the Apostle Paul’s letters, Christians are no longer subject to the divine requirements of the Mosaic Law, such as the observance of a mandatory Sabbath or a new moon marking a new month. Indeed, Christians are no longer under the authority of the Law: « For Christ is the end of the Law, so that everyone exercising faith may have righteousness » (Romans 10:4). Thus, the above explanations regarding the two kinds of new moon are not to be understood in the context of the application of the Law.
The importance of the matter about the new moon depends on the purpose of this information. If the question is how to determine the date of the next commemoration of Christ’s death on a biblical basis, some will base their calculations on the astronomical new moon, while others will simply rely on the classical Hebrew calendars, which take into account the religious new moon. There is usually a difference of one or two days.
As for the date of the commemoration of Christ’s death, it is all a matter of discernment (Hebrews 5:14 « Their powers of discernment trained to distinguish both right and wrong »). Based on the discernment of the biblical context, we understand that the commemoration should be celebrated once a year (and not every Sunday): « Christ our Passover lamb has been sacrificed » (1 Corinthians 5:7). This text shows that the celebration of the commemoration replaced the celebration of the Jewish Passover, which was celebrated, in biblical times, between the two evenings of Nisan 13 and 14 (after sunset on Nisan 13 and before sunrise on Nisan 14).
Regarding the kind of new moon, apart from the technical explanations above, there is no direct indication in the Bible as to which new moon it is (either religious or astronomical). Therefore, it is up to each Christian, each Christian congregation, or the administrators of these congregations to decide how to calculate the date of the annual commemoration of Christ’s death (from the astronomical new moon or the religious new moon). The important thing, of course, is to obey Christ’s command to commemorate his sacrificial death: « Keep doing this in remembrance of me » (Luke 22:19).
A Vital Issue
Nevertheless, the matter of the type of new moon can be very important, even vital. We are currently awaiting the return of Christ to judge all of humanity shortly before the Great Tribulation (Matthew 25:31-42). Regarding this day, in an early statement, Jesus Christ said, no one knows the day or the hour: « Concerning that day and hour nobody knows, neither the angels of the heavens nor the Son, but only the Father » (Matthew 24:36). This statement was made in 33 C.E.
Was such ignorance going to be permanent? Regarding Jesus Christ, it is obvious that it was not, because shortly before ascending into heaven, this is what he declared: « Jesus approached and spoke to them, saying: “All authority has been given me in heaven and on the earth » » (Matthew 28:18). Furthermore, in the book of Apocalypse Jesus Christ is described as a king and high priest who will bring about the great tribulation (Apocalypse 19). How can we imagine that, as a king who has all power, he would have been kept in ignorance by his Heavenly Father of such a Day?
Furthermore, concerning his disciples, here is what we can read in the book of Apocalypse, in his message addressed to the congregation of Sardis, more than sixty years after his first declaration on the ignorance of the day and hour: « Certainly unless you wake up, I will come as a thief, and you will not know at all at what hour I will come upon you » (Apocalypse 3:3). This text implies that the spiritually awakened disciples would end up at the time chosen by God, knowing the exact day and hour of the coming of Christ: « For the Sovereign Lord Jehovah will not do a thing Unless he has revealed his confidential matter to his servants the prophets » (Amos 3:7).
Returning to the theme of what kind of new moon it is, we are faced with a real dilemma. While Jesus Christ declared that his coming, foreseen by God, would be on a specific day and time, how can we know this when the astronomical new moon is one to two days ahead of the religious new moon. Which one should we choose? The logic is to choose the new moon that is two days ahead (the astronomical new moon), rather than choosing a new moon that is two days behind (the religious new moon). If we have a vital appointment, it is better to be early and, on the lookout, rather than to be late. Moreover, Jesus Christ clearly showed that any delay would have a fatal outcome:
« Then the Kingdom of the heavens may be likened to ten virgins who took their lamps and went out to meet the bridegroom. 2 Five of them were foolish, and five were discreet. 3 For the foolish took their lamps but took no oil with them, 4 whereas the discreet took oil in their flasks along with their lamps. 5 While the bridegroom was delaying, they all became drowsy and fell asleep. 6 Right in the middle of the night there was a shout: ‘Here is the bridegroom! Go out to meet him.’ 7 Then all those virgins got up and put their lamps in order. 8 The foolish said to the discreet, ‘Give us some of your oil, because our lamps are about to go out.’ 9 The discreet answered, saying: ‘Perhaps there may not be enough for both us and you. Go instead to those who sell it, and buy some for yourselves.’ 10 While they were going off to buy it, the bridegroom came. The virgins who were ready went in with him to the marriage feast, and the door was shut. 11 Afterward, the rest of the virgins also came, saying, ‘Sir, Sir, open to us!’ 12 In answer he said, ‘I tell you the truth, I do not know you’ » (Matthew 25:1-12).
Jesus Christ concluded his illustration by saying, « Keep on the watch, therefore, because you know neither the day nor the hour » (Matthew 25:13). This text shows that even if we have solid indications of the day and hour, there is no absolute certainty based on our personal understanding. We must remain vigilant in waiting for this moment so as not to be surprised by the coming of King Jesus Christ to judge humanity (Matthew chapters 24 and 25; Apocalypse 3:3).
***
The Fulfillment of the Planetary Jubilee (Hebrews 10:1)
The Jubilee is a liberation from a slavery, which is that of sin and death (Romans 5:12)…
The Fulfillment of the Planetary Day of Atonement (Yom Kippur) and the Great Tribulation (Hebrews 10:1)
The Great Tribulation will be a tragic time of the end of this system of things…
The book of Ezekiel mentions that the year in which the Great Tribulation will occur should be lunisolar, with 13 months, according to the Jewish calendar…
This period of 2300 evenings and mornings refers to a period of time lasting several years, which describes a behavior that goes directly against the sacred service rendered to God, in the holy place of the Spiritual Temple Sanctuary…
This study will focus primarily on the 1335 days related to Ethanim (Tishri), 10, beginning the calculation with the latter date and working backward to the original date of the Hebrew biblical calendar…
The Great Tribulation Will Take Place In Only One Day (Zechariah 14:16)
According to Zechariah’s prophecy, the Day of Jehovah, the Great Tribulation, will last only one day…
How To Be Prepared Before The Great Tribulation
This is a simple spiritual preparation of the heart before the Great Tribulation…
***
Table of contents of the http://yomelyah.fr/ website
Reading the Bible daily, this table of contents contains informative Bible articles (Please click on the link above to view it)…
Table of languages of more than seventy languages, with six important biblical articles, written in each of these languages…
***