"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 important question is what is written in the Bible to help us to understand what the new
moon is. Psalm 81:3 allows us to have a precise answer.
This text shows that the first day of the month, on the "new moon" was announced by the blowing the horn. And then, the Psalm
informs that on the "full moon" was celebrated the day of a "festival". The context can allow us to know what were this festival and its date. With this information we can know what new moon it is.
Before that, based on the astronomical table of the lunar cycle of November 2018 (as example), we must know that the complete disappearance of the moon (without crescent), usually lasts three nights (see the illustration: the nights of 7,8,9). The two
letters in blue "NL", is the moment when the moon emits the least residual light and consequently it is considered as New Moon (by astronomical measure). It is usually between the first and the second moonless night. Nevertheless, by putting ourselves in the
place of humans who had no astronomical instrument of measurement, it is logical to think that, in the case where the new moon was at the time of the moonless night, the new moon was logically the first moonless night.
And the full moon, the fully enlightened moon (whatever the intensity of the sunlight), lasts three nights (22,23,24 (example)). Applying the same logic of a human without an astronomical measuring instrument, the full the moon was
the first night when the moon appears fully, that is, in this example, on November 22nd.
The context of Psalm 81 suggests that was the festival of booths with a trumpet blast (or horn)
at Tishri 1st: "Tell the Israelites, ‘In the seventh month, on the first of the month, you should observe a complete rest, a memorial signaled by a trumpet blast, a holy convention" (Leviticus 23:24). Then in Tishri 15th was the festival of booths (Leviticus
23:34). Regarding this festival Jehovah had ordained: "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 compare with Psalm 81:1,2 "Shout joyfully to God our strength. Shout in triumph to the God of Jacob").
If the 15th of the month represents the full moon (whether
it is the first day or the second day (full moon)), going up we reach the first day, the new moon, the moonless night. This option (of the new moon (moonless night)) was retained by the current Hebrew calendar. And it is interesting to note that the Christians
who calculated the date of October 4/5, 1914, as the date of the enthronement of Christ in heaven, Tishri 15th (4/5 October 4/5th), have also retained this new moon option (moonless night (not the first crescent)). By the way, the method of considering the
new moon by the first visible crescent depends on the geographical location where one is. So the schedule could vary from one day depending on the geographical location where the observer would be ...
The option of the new moon, the moonless night, (and not that of the first crescent moon (which has no biblical basis)), conforms to the Bible. This option was chosen by the Hebrew calendar and it is on this basis that the date of the commemoration of the death of Christ (which is mainly based on the current Hebrew calendar) is calculated and the determination of the date of Tishri 10th.
THE LAST KING