The Metonic cycle is a period of 19 years, after which the lunar phases recur at the same time of the year. The recurrence is not perfect, and by precise observation, the Metonic cycle defined as 235 synodic months is just 2 hours, 4 minutes, and 58 seconds longer than 19 tropical years. The lunar month is when the Moon completes one cycle of phases, from the New Moon to the New Moon. This cycle was found to be a nearly exact match for 19 solar years (19 years x 365.2422 days = 6939.6 days). It will drift by one day over time (approximately 200-300 years).
In my article, The Passage of Time (rev310.net), I wrote, "Mathematical calculations played a crucial role in developing and implementing the Metonic Cycle. These mathematical calculations determined the accuracy and duration of the Metonic Cycle. By aligning the solar and lunar calendars, the Metonic Cycle ensured that the phases of the moon and the seasons of the year remained synchronized. This synchronization was achieved by adding seven intercalary months (30 days) to the 19-year cycle, compensating for the fractional difference between the lunar and solar years. The mathematical genius behind the Metonic Cycle allowed for an accurate and practical calendar system."
An embolismic year has 13 new moons (likewise 13 months) between two spring (meteorological) seasons, so instead of having the regular 353-355 days per year, it has 383-385 days per year. This occurs seven out of the 19 years of the Metonic cycle, approximately every two to three years. Regarding the Hebrew calendar, the rule to determine the first month of the new year should be the new moon that establishes Passover (Nisan 14-15) on or after the Vernal Equinox. The first month (Nisan) is the new moon closest to the Vernal Equinox, whether the new moon is before or after the Vernal Equinox (March 19-21).
In Deuteronomy 16:6, the LORD reiterated, “You shall sacrifice the Passover at twilight, at the going down of the sun, at the time you came out of Egypt.” At the original Passover, in 1446 BC, God changed the Hebrew calendar's start to be permanently anchored to the Passover when the children of Israel came out of Egypt.
“Let the children of Israel also keep the passover at his appointed season. In the fourteenth day of this month, at even, you shall keep it in his appointed season: according to all the rites of it, and according to all the ceremonies thereof, shall you keep it” (Numbers 9:2-3). In my article, The Flaw in the Calculated Jewish Calendar (rev310.net), I wrote, "The appointed season was the beginning of spring. The sun still determined the season, as the calendar’s first month would always occur around the vernal equinox (the first day of the astronomical spring) when the early barley crops were abib or aviv. The new moon would still begin the months, and approximately 14-15 days later, when the moon was completely full, the Passover would begin. Thus, Passover is tied to the vernal equinox and the full moon."
New Moon Patterns in the Jewish Calculated Calendar
Most of the time (16 out of 19 years), the first new moon of meteorological spring (March 1 - May 31) is used for the year's first month. Even when a lunar year is between two first new moons of spring, it can still be an embolismic (or intercalary) year. Let’s look at a recent example. The first new moon (conjunction) of spring in 2019 was on March 6 (the second one was on April 5). March 6 was the first month because the Passover (which comes on a full moon) falls after the Vernal Equinox (barely). The following year's new moon was on March 24, 2020. March 24 is the first new moon of the meteorological spring season of 2020 (the second one was on April 23). From March 6, 2019, to March 24, 2020, is 384 days, an embolismic year.
It will always be an embolismic year when you go from the first new moon of spring to the following year's second new moon of spring. However, it will always be a regular year when you go from the second new moon of spring to the following year's first new moon of spring.
An interesting pattern emerges when you reckon the start of the new year by whether it begins on the first new moon of spring (must be on or after the start of meteorological spring – March 1) or if it begins on the second new moon of spring.
The pattern (which is consistent for hundreds of years) for the new moons of spring (whether the first or second new moon of spring) is seven (first new moons), one (second new moon), seven (first new moons), one (second new moon), two (first new moons), and one (second new moon) and then repeats continuously. After hundreds of years, the pattern of 7, 1, 7, 1, 2, 1 remains within the Metonic cycle, but the order within the pattern changes. See below.
The tables below contain two consecutive 19-year Metonic cycles. The sub-headings show the new moon conjunction dates (from Jerusalem) for the specified years and whether the new moon that starts the year is the first or second new moon of spring (meteorological), as reckoned by our "golden rule." The table also shows the dates for the full moon of Passover and the Vernal Equinox dates for the specified years. Passover must be on or after the Vernal Equinox.
20-21ST CENTURY LUNAR MONTHS (Order of Pattern - 7, 1, 7, 1, 2, 1)
NEW MOON FIRST OR SEC. FULL MOON OF VERNAL EQUINOX
DATE
NEW MOON THE PASSOVER DATE
19) Mar 19, 1996 First April 4, 1996 Mar 20, 1996
1) Mar 9, 1997 First Mar 24, 1997 Mar 20, 1997
2) Mar 28, 1998 First Apr 12, 1998 Mar 21, 1998
3) Mar 17, 1999 First April 1, 1999 Mar 21, 1999
4) Mar 6, 2000 First Mar 20, 2000 Mar 20, 2000
5) Mar 25, 2001 First April 8, 2001 Mar 20, 2001
6) Mar 14, 2002 First Mar 28, 2002 Mar 21, 2002
7) April 2, 2003 Second Apr 17, 2003 Mar 21, 2003
8) Mar 21, 2004 First April 5, 2004 Mar 20, 2004
9) Mar 10, 2005 First Mar 26, 2005 Mar 20, 2005
10) Mar 29, 2006 First Apr 13, 2006 Mar 21, 2006
11) Mar 19, 2007 First April 2, 2007 Mar 21, 2007
12) Mar 7, 2008 First May 22, 2008 Mar 20, 2008
13) Mar 26, 2009 First April 9, 2009 Mar 20, 2009
14) Mar 16, 2010 First Mar 30, 2010 Mar 20, 2010
15) April 3, 2011 Second Apr 18, 2011 Mar 21, 2011
16) Mar 22, 2012 First April 7, 2012 Mar 20, 2012
17) Mar 12, 2013 First Mar 27, 2013 Mar 20, 2013
18) April 1, 2014 Second Apr 15, 2014 Mar 20. 2014
19) Mar 20, 2015 First April 4, 2015 Mar 21, 2015
1) Mar 9, 2016 First Mar 23, 2016 Mar 20, 2016
2) Mar 28, 2017 First Apr 11, 2017 Mar 20, 2017
3) Mar 17, 2018 First Mar 31, 2018 Mar 20, 2018
4) Mar 6, 2019 First Mar 21, 2019 Mar 21, 2019
5) Mar 24, 2020 First April 8, 2020 Mar 20, 2020
6) Mar 13, 2021 First Mar 28, 2021 Mar 20, 2021
7) April 1, 2022 Second Apr 17, 2022 Mar 20, 2022
8) Mar 21, 2023 First April 6, 2023 Mar 21, 2023
9) Mar 10, 2024 First Mar 25, 2024 Mar 20, 2024
10) Mar 29, 2025 First Apr 13, 2025 Mar 20, 2025
11) Mar 19, 2026 First April 2, 2026 Mar 20, 2026
12) Mar 8, 2027 First Mar 22, 2027 Mar 21, 2027
13) Mar 26, 2028 First April 9, 2028 Mar 20, 2028
14) Mar 15, 2029 First Mar 30, 2029 Mar 20, 2029
15) April 3, 2030 Second Apr 18, 2030 Mar 20, 2030
16) Mar 23, 2031 First April 7, 2031 Mar 21, 2031
17) Mar 11, 2032 First Mar 27, 2032 Mar 20, 2032
18) Mar 30, 2033 Second Apr 15, 2033 Mar 20, 2033
19) Mar 20, 2034 First April 4, 2034 Mar 20, 2034
1) Mar 10, 2035 First Mar 24, 2035 Mar 21, 2035
25TH CENTURY LUNAR MONTHS (Order of Pattern - 7, 1, 2, 1, 7, 1)
19) Mar 22, 2433 First April 5, 2433 Mar 20, 2433
1) Mar 11, 2434 First Mar 25, 2434 Mar 20, 2434
2) Mar 30, 2435 First Apr 13, 2435 Mar 21, 2435
3) Mar 18, 2436 First April 2, 2436 Mar 20, 2436
4) Mar 7, 2437 First Mar 22, 2437 Mar 20, 2437
5) Mar 26, 2438 First Apr 10, 2438 Mar 20, 2438
6) Mar 15, 2439 First Mar 31, 2439 Mar 21, 2439
7) April 2, 2440 Second Apr 18, 2440 Mar 20, 2440
8) Mar 23, 2441 First April 7, 2441 Mar 20, 2441
9) Mar 13, 2442 First Mar 27, 2442 Mar 20, 2442
10) April 1, 2443 Second Apr 15, 2443 Mar 21, 2443
11) Mar 20, 2444 First April 3, 2444 Mar 20, 2444
12) Mar 9, 2445 First Mar 24, 2445 Mar 20, 2445
13) Mar 28, 2446 First Apr 12, 2446 Mar 20, 2446
14) Mar 17, 2447 First April 1, 2447 Mar 20, 2447
15) Mar 5, 2448 First Mar 21, 2448 Mar 20, 2448
16) Mar 24, 2449 First April 8, 2449 Mar 20, 2449
17) Mar 14, 2450 First Mar 28, 2450 Mar 20, 2450
18) April 2, 2451 Second Apr 16, 2451 Mar 20, 2451
19) Mar 21, 2452 First April 4, 2452 Mar 20, 2452
1) Mar 10, 2453 First Mar 25, 2453 Mar 20, 2453
2) Mar 29, 2454 First Apr 13, 2454 Mar 20, 2454
3) Mar 18, 2455 First April 3, 2455 Mar 20, 2455
4) Mar 7, 2456 First Mar 22, 2456 Mar 20, 2456
5) Mar 26, 2457 First Apr 10, 2457 Mar 20, 2457
6) Mar 15, 2458 First Mar 30, 2458 Mar 20, 2458
7) April 3, 2459 Second Apr 18, 2459 Mar 20, 2459
8) Mar 23, 2460 First April 6, 2460 Mar 20, 2460
9) Mar 12, 2461 First Mar 26, 2461 Mar 20, 2461
10) Mar 31, 2462 Second Apr 14, 2462 Mar 20, 2462
11) Mar 20, 2463 First April 4, 2463 Mar 20, 2463
12) Mar 8, 2464 First Mar 24, 2464 Mar 20, 2464
13) Mar 27, 2465 First Apr 12, 2465 Mar 20, 2465
14) Mar 17, 2466 First April 1, 2466 Mar 20, 2466
15) Mar 6, 2467 First Mar 21, 2467 Mar 20, 2467
16) Mar 24, 2468 First April 8, 2468 Mar 20, 2468
17) Mar 14, 2469 First Mar 28, 2469 Mar 20, 2469
18) April 2, 2470 Second Apr 16, 2470 Mar 20, 2470
19) Mar 22, 2471 First April 5, 2471 Mar 20, 2471
1) Mar 10, 2472 First Mar 25, 2472 Mar 20, 2472
In the 25th century Metonic cycle, the pattern remains the same for the new moons of spring (whether the first or second new moon of spring), but the order has changed. The change occurs in the 10th and 15th years of the Metonic cycle. The order of the pattern is now 7, 1, 2, 1, 7, 1 or seven (first new moons), one (second new moon), two (first new moons), one (second new moon), seven (first new moons), one (second new moon), and then repeats continuously. After hundreds of years, this pattern persists, but the order within the Metonic cycles will change eventually.
The seven embolismic years (with 383-385 days) for the first Metonic cycle of the Hebrew calendar (with our rules in place) are #1 (2434-2435), #4 (2437-2438), #6 (2439-2340), #9 (2442-2443), #12 (2445-2446), #14 (2447-2448), and #17 (2450-2451). The same embolismic pattern of 1, 4, 6, 9, 12, 14, 17 are found in the second Metonic cycle: #1 (2453-2454), #4 (2456-2457), #6 (2458-2459), #9 (2461-2462), #12 (2464-2465), #14 (2466-2467), and #17 (2469-2470).
The current (and original) embolismic pattern for the calculated (Metonic) Jewish calendar is 3, 6, 9, 11, 14, 17, 19. It was reasonably accurate back when it was created in the fourth century AD, but with time, it has gotten off track. As you can see, their embolismic years are only correct four out of seven times currently. That means there are four times in the Metonic cycle that the Jewish calendar uses the second new moon of spring for the beginning of the new year when it should have used the first new moon of spring. The "golden rule" for determining the first month of the year (the first month of the new year is the new moon that establishes Passover on or after the Vernal Equinox) is no longer accurate 100% of the time. The result of this inaccuracy in the Jewish calendar for these particular years is the Feast of the Lord convocations will occur one month late.
When (not if) the Jews build their third temple in Jerusalem, will they be worshipping the LORD and offering sacrifices on the correct Feast of the Lord days as specified in Leviticus 23? Scripture clearly indicates there will be a third temple for the Jews in the end times. “Let no one deceive you by any means; for that Day will not come unless the falling away comes first, and the man of sin is revealed, the son of perdition, who opposes and exalts himself above all that is called God or that is worshiped, so that he sits as God in the temple of God, showing himself that he is God”
(2 Thessalonians 2:3-4).
Randy Nettles
Great question, time will tell. God bless