ASHORTWORK
Biblical Understanding based on the Record of Scripture
YHVH created the sun and the moon and set them in the heavens, in part, to show when to observe His Festivals. The date listed on this calendar for the start of the 1st month and the 7th month is based on the first projected sighting, after sunset, of the renewing of the light of the moon.
Leviticus 23:33-36 NKJV
Then Yehovah spoke unto Moses, saying,
the fifteenth day of this seventh month shall be the Feast of Tabernacles for seven days to Yehovah.
On the first day there shall be a holy convocation. You shall do no customary work on it.
For seven days you shall offer and offering made by fire to Yehovah. On the eighth day you shall have a holy convocation, and you shall offer an offering made by fire to Yehovah. It is a sacred assembly, and you shall do no customary work on it.
(Also see verses 39-44)