The Biblical Calendar According to the Sages of the Dead Sea Scrolls of Qumran: Including the Books of Enoch and Jubilees also found there, which are also a part of the Canon of Scriptures of Ethiopian Jews and Christians:
4-Seasons with an intercalary day between each season (91 Days each);
12 Months of 30 Days; 52-Weeks; totaling 364-Days and Nights;
The “Day out of Time” to make the 365th Day is on the 22nd of the 7th Month; Added by Ya’aqoḅ (Jubilees 32:27), aka Shemini Atzeret & Simchat Torah;
Festivals fall on the same day of the week every year;
There is an intercalation week every 7 years,
an extra week at 49 years & 70 years, staying in sinc to
less than a minute 365.2529 Days with the 365.2522 Day Solar Year;
It is not based upon the phases of the Moon, where
a 13th month is added every 2-3 years—7 times in 19 years.

Accordingly, the New Year begins in the Spring—not,
in the Summer, and not in the Fall, and not in the Winter.

Rosh ha’Shanah in the Spring

Ex 12:2 “This ḥodesh [a constellation month at the spring equinox] shall be for you the beginning (rosh) of ḥodeshim [the 12 months according to the 12 constellations].
It shall be the first (rishon) month of the year (shanah) for you.

Dt. 16:1  “Guard the odesh of Aḅiḅ [Spring], and observe
the Pesách to YHWH your Elo’ah: for in the month of Aḅiḅ
YHWH your Elo’ah brought you forth out of Egypt by night.”

The word for Moon (Yare`ach) does not appear here in these verses. It is not a correct translation of ḥodesh, although Bible translators translate it as such by erroneous tradition.

H2318 חָדַשׁ chadash (chaw-dash’) v. 1. to be new. 2. (causatively) to rebuild. [a primitive root] KJV: renew, repair.
H2320 חֹדֶשׁ chodesh (cho’-desh) n-m. 1. the new moon. 2. (by implication) a month. [from H2318]
H3394  יָרֵחַ  yareach (yaw-ray’-ach) n-m. the moon.

Again, this is a constellation month based upon the motion of the Sun as it moves north and south during the year. It enters a new constellation, marked as a 30-Day Month—12 months per year and 4-seasons—Spring, Summer, Autumn, and Winter.

Later Priests and Pharisees altered this. They adopted from Babylon and Greece, either during the Maccabean or Herodian period. They began to call Yom Teruah “Rosh ha’Shanah” as they established a Civil year along with the Festival year, and counting their years by it. However, according to Scripture, the 1st Day of the 7th month is at the end of the Summer and is called “Yom Teruah” — not Rosh ha’Shanah. (Lev. 23:24) They also began to start a new day at night rather than in the morning. Throughout the Scriptures, however, there was a Morning-Day-Evening-Night sequence. (Arguments used to prove the Moon based Calendar by using a few Psalmic passages will be refuted at the end of this page. There, the proper translation and context is made clear concerning these passages: Ps 89:37; 136:9; 104:19; 81:3.)

What Do the Jewish Sages of the Book of Enoch Say?

Enoch 72:29-33 “…So the sun has returned and entered into the second window in the east, and returns orbital divisions for thirty mornings, rising and setting. On that day, the night decreases in length. The night amounts to ten parts and the day to eight. On that day, the sun rises from that window, sets in the west, returns to the east, and rises in the third window for thirty-one mornings before it sets in the western sky. On that day, the night decreases and amounts to nine parts, the day to nine parts; the night is equal to the day and the year is exactly three hundred sixty-four days.”

Note also, that in the books of Daniel and Revelation, the 360-Day year (with 4 seasonal division days that are not part of the count) is described as a “time and times and half a time” and “forty-two months” and 1260 days, which equals 3½ years = 42 months ÷ by 12 = 3½ years). 360 Days ÷ 12 Months = 30 Days per month.

What Does Jewish Sages of the Book of Jubilees say?

Jubilees 2:8-10   And on the fourth day [Wednesday – Day 1 of the New Year} He created the sun and the moon and the stars, and set them in the firmament of the heavens, to give light upon all the earth, and to rule over the day and the night, and divide the light from the darkness. And God appointed the sun {not the moon} to be a great sign on the earth for Days and for Sabbaths and for Months and for Feasts and for Years and for Sabbaths of Years and for Jubilees and for all Seasons of the Years. 10. And it divides the light from the darkness [and] for prosperity, that all things may prosper which shoot and grow on the earth. These three kinds He made on the fourth day…

Jubilees 6:30-34   And all the days of the commandment will be fifty-two weeks of days, and (these will make) the entire year complete.  Thus it is engraved and ordained on the heavenly tables. And there is no neglecting (this commandment) for a single -year or from year to year. And command you the children of Israel that they observe the years according to this reckoning-three hundred and sixty-four days, and (these) will constitute a complete year, and they will not disturb its time from its days and from its feasts; for everything will fall out in them according to their testimony, and they will not leave out any day nor disturb any feasts.  But if they do neglect and do not observe them according to His commandment, then they will disturb all their seasons, and the years will be dislodged from this (order), [and they will disturb the seasons and the years will be dislodged] and they will neglect their ordinances. And all the children of Israel will forget, and will not find the path of the years, and will forget the new-months {chodesh = 30 day monthly renewal, not yareach = moon phases}, and Seasons, and Sabbaths, and they will go wrong as to all the order of the years. 

35-38 For I know and from henceforth shall I declare it unto you, and it is not of my own devising; for the book (lies) written before me, and on the heavenly tables the division of days is ordained, lest they forget the feasts of the covenant and walk according to the feasts of the Gentiles after their error and after their ignorance. For there will be those who will assuredly make observations of the moon–now (it) disturbs the seasons and comes in from year to year ten days too soon. For this reason the years will come upon them when they will disturb (the order), and make an abominable (day) the day of testimony, and an unclean day a feast day, and they will confound all the days, the holy with the unclean, and the unclean day with the holy; for they will go wrong as to the months and Sabbaths and Feasts and Jubilees. For this reason I command and testify to thee that you may testify to them; for after thy death thy children will disturb (them), so that they will not make the year three hundred and sixty-four days only, and for this reason they will go wrong as to the New-Months (chodesh, not yareach) and Seasons and Sabbaths and Festivals, and they will eat all kinds of blood with all kinds of flesh.

Enoch Chapter 82 (Enoch summarizes, chapters 72-81, for his son the motions of the sun, moon, and stars)

Enoch 82:1-3   And now, my son Methuselah, all these things I am recounting to thee and writing down for thee! and I  have revealed to thee everything, and given you books concerning all these: so preserve, my son Methuselah, the books from thy father’s hand, and (see) that thou deliver them to the generations of the world. I have given wisdom to thee and to thy children, [And thy children that shall be to thee], That they may give it to their children for generations, This wisdom (namely) that passes their thought. And those who understand it shall not sleep, But shall listen with the ear that they may learn this wisdom, And it shall please those that eat thereof better than good food.

4-10 Blessed are all the righteous, blessed are all those who walk in the way of righteousness and sin not as the sinners, in the reckoning of all their days in which the sun traverses the heaven, entering into and departing from the portals for thirty days with the heads of thousands of the order of the stars, together with the four which are intercalated which divide the four portions of the year, which lead them and enter with them four days. Owing to them men shall be at fault and not reckon them in the whole reckoning of the year: yea, men shall be at fault, and not recognize them accurately. For they belong to the reckoning of the year and are truly recorded (thereon) forever, one in the first  portal and one in the third, and one in the fourth and one in the sixth, and the year is completed in three hundred and sixty-four days. And the account thereof is accurate and the recorded reckoning thereof exact; for the luminaries, and months and festivals, and years and days, has Uriel shown and revealed to me, to whom the Lord of the whole creation of the world hath subjected the host of heaven. And he has power over night and day in the heaven to cause the light to give light to men -sun, moon, and stars, and all the powers of the heavens which revolve in their circular chariots. And these are the orders of the stars, which set in their places, and in their seasons and festivals and months.

10-14 And these are the names of those who lead them, who watch that they enter at their times, in their orders, in their seasons, in their months, in their periods of dominion, and in their positions. Their four leaders who divide the four parts of the year enter first; and after them the twelve leaders of  the orders who divide the months; and for the three hundred and sixty (days) there are heads over thousands who divide the days; and for the four intercalary days there are the leaders which divide the four parts of the year. And these heads over thousands are intercalated between leader and leader, each behind a station, but their leaders make the division. And these are the names of the leaders who divide the four parts of the year which are ordained: Mîlkî’êl, Hel’emmêlêk, and  Mêl’êjal, and Nârêl. And the names of those who lead them: Adnâr’êl, and Ijâsûsa’êl, and ‘Elômê’êl -these three  follow the leaders of the orders, and there is one that follows the three leaders of the orders which follow those leaders of stations that divide the four parts of the year.

15-17 In the beginning of the year Melkejâl rises first and rules, who is named Tam’âinî and sun, and all the days of his dominion whilst he bears rule are ninety-one days. And these are the signs of the days which are to be seen on earth in the days of his dominion: sweat, and heat, and calms; and all the trees bear fruit, and leaves are produced on all the trees, and the harvest of wheat, and the rose-flowers, and all the flowers which come forth in the field, but the trees of the winter season become withered. And these are the names of the leaders which are under them: Berka’êl, Zêlebs’êl,  and another who is added a head of a thousand, called Hîlûjâseph: and the days of the dominion of  this (leader) are at an end.

18-20 The next leader after him is Hêl’emmêlêk, whom one names the shining sun, and all the days of his light are ninety-one days. And these are the signs of (his) days on the earth: glowing heat and dryness, and the trees ripen their fruits and produce all their fruits ripe and ready, and the sheep pair and become pregnant, and all the fruits of the earth are gathered in, and everything that is in the fields, and the winepress: these things take place in the days of his dominion. These are the  names, and the orders, and the leaders of those heads of thousands: Gîdâ’îjal, Kê’êl, and Hê’êl, and the name of the head of a thousand which is added to them, Asfâ’êl: and the days of his dominion are at an end.

One Jubilee = 49 Years | From Creation to the Promised Land is 49 x 50 = 2450 Years (Book of Jubilees)

Proper Translation and Orientation of the Psalms
Passages of Purported Moon Verses

Once have I sworn by my holiness that I will not lie unto David. 36 His seed shall endure for ever, and his throne as the sun before me. 37 IT shall be established forever as the moon (yareach), and as a faithful witness in the heavens. Selah.

Psalm 89:35

In verse 37, “IT” refers to the promise for David’s seed and his throne in verses 35-36. David’s seed and throne shall be established forever like the moon, as it is a faithful witness preserved in the heavens. This verse does not claim that the moon is forever faithful for telling time.

The Moon (Yare’ach) and Stars (Kochavim) to rule by night: for His mercy endures forever.

Psalm 136:9

This verse says that the Moon and Stars rule the night as is also clear from Genesis 1:14-18. Nothing here concerning the Moon governing our Calendar. Jubilees makes this abundantly clear.

He created the Moon (Yare’ach) for Appointed-Times-Activities: the Sun knows its going down. 20 You make darkness, and it is night: in it all the beasts of the forest do creep. 21 The young lions roar after their prey, and seek their food from EL. 22 The sun arises, they gather themselves together, and lay themselves down in their dens. 23 Man goes forth unto his work and to his labour until the evening (Erev – Dusk).

Psalm 104:19-23

This does not refer to the festivals (chagim) of YHWH as is claimed by some. The light of the Moon shining during the night signals night creatures to hunt for their food until Sunrise. These verses have nothing to do with scriptural Appointed-times for the gathering of His people, which we have shown are dependent upon the Sun, as shown with the passages quoted earlier.

Blow a shofar in the Hodesh, in fullness (Keseh) for our festival (Chag).
Blow a shofar in/at the Hodesh (the spring month beginning a New Year); Blow it in/at the fullness (Keseh / Nes – signal) for our festival (Chag of Pesach).

Psalm 81:3

There are, specifically, eight Appointed-Times (Mo’edim) for Assembly mentioned in Leviticus 23, counting the Weekly Sabbath Day; But, only three of them are also called, Chagim or Festivals; And those three are: (1) Pesach-Matsa, (2) Shavuot, and (3) Sukkot, or, (1) The Week of Passover-Unleavened Bread in the Spring, (2) The Day of Pentecost toward the end of Spring and, (3) The Week of Tabernacles in the Autumn). The context in Psalm 81 indicates that “our-Chag” specifically refers to Israel’s deliverance and coming out of Egypt, which happened during the week of Passover-Unleavened Bread and it is especially related to it as its memorial. The word Keseh is difficult here as one will find out by doing a word study. Keseh carries the idea of fullness or a covering as in clothing or of a canopy over a throne and comes from the verb, Kasah – to plump, or to cover. It is pointed out that there may be a copyists mistake, turning Neseh into Keseh (from a נ to a כ). The Neseh is related to Nes – a banner, flag, a sign, providing a signal, announcing the month of and/or the day of the Festival.

The word for Moon, Yare’ach, appears nowhere in Psalm 81 nor the term “full moon.” The Pharisees-Rabbis, followed by Christians, translate it as full moon. This lunar calendar, however, was forced upon Judaism by Antiochus Epiphanies, and then by the Pharisees following the Maccabean victory over him.