Hebrew Calendar - Chiourim - May 2019 (written in french) (Nisan / Iyar 5779):
Two days late with the biblical system of the new moon (Psalms 81:3)
"Blow the horn on the new moon, On the full moon, for the day of our festival"
There are two definitions of the new moon:
1 - "The new moon is the first lunar phase,
when the Moon and Sun have the same ecliptic longitude. At this phase, the lunar disk is not visible to the unaided eye, except when silhouetted during a solar eclipse. Daylight outshines the earthlight that dimly illuminates the dark side of the new Moon.
The actual phase is usually a very thin crescent because the Moon rarely passes directly in front of the Sun, except in a solar eclipse" (Wikipedia New Moon).
2 - "The original meaning of the term new moon, which is still sometimes used in non-astronomical
contexts, was the first visible crescent of the Moon, after conjunction with the Sun. This crescent Moon is briefly visible when low above the western horizon shortly after sunset and before moonset" (Wikipedia New Moon).
The first definition of the new moon, is corroborated by what is written in Psalms 81:3: "Blow the
horn on the new moon, On the full moon, for the day of our festival". According to the context of this Psalm, it is the festival of booths which was celebrated from Ethanim 15th (Tishri 15) to Ethanim 22nd. It was an autumn festival, in the time of the last
harvests. While the festival of unfermented cakes, was celebrated from Nisan 15 to 22, in the spring, at the beginning of the first harvests.
In Psalms 81:1 it is written: "Shout joyfully
to God our strength. Shout in triumph to the God of Jacob". The festival that most symbolized the joy and exuberance, was undoubtedly the fest of booths. Regarding it, Jehovah had told Moses, for his people Israel: "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 16:15 (see verse 13)). The expression of Psalms 81, "Shout joyfully to God our
strength", describes perfectly the feeling of joy asked by God, in Deuteronomy 16:15. The complete appearance of the "full moon", marking the middle of the lunar month, is in the poetic contrast to the "new moon", which is at this stage, invisible, and represents
the start of the month.
By the way, if you look at the astronomical table of the lunar cycle, you will notice that the full moon lasts about three nights, and the new moon, its disappearance,
for three nights, in general. It is also interesting to note that David, fleeing from before king Saul, associated the new moon with three days during which he could hide (1 Samuel 20: 5). Is it a simple coincidence? Not necessarily, if one thinks of the three
moonless nights, the period of the "new moon", allowing him to hide safely, without being surprised in his sleep.
Regarding Psalms 81:1,3, the astronomical tables of the lunar cycles,
if we go back, starting from the full moon (whether it's the Tishri, 15 or the Nisan, 15), we arrive at the beginning of the month, at the new moon, at the moment "when the Moon and Sun have the same ecliptic longitude" and therefore, it is invisible (http://pgj.pagesperso-orange.fr/calendar.htm). In the example presented in the photo (above),
of the lunar cycle of May 2019: After the sunset of May, 17 to May 18, is the full moon, biblically speaking, the 15th of the month of "Iyyar" (or Ziv), of the Hebrew month. Going back fifteen days, we reach the date of Iyyar 1st (biblical month), May 3rd,
2019 (gregorian calendar), after sunset.
Nevertheless, in the current Hebrew calendar (Hebrew Calendar - Chiourim (In French)), Iyyar 1st is after the sunset of May 5th to May 6, 2019,
there are two days late (See photo to the right). In this case, it is the chosen option of "the first visible crescent of the Moon" (see photo above, comparing it to the Hebrew Calendar (in Jerusalem). What option to choose? The invisible new moon or the first