EDITED 1/25/17: See Notes in Red.
Recently I received an email that read: 
I have been thinking about the start of the year and wondered how you determine the beginning of the year using a solar calendar.
Here was my response:
From what I understand from the Book of Enoch, the years are solar in nature one year with the has months being determined by way of the sun rising in 6 different stations of the sky in the east and setting in 6 in the west (marked by the 12 constellations of the stars), and the moon likely plays a part in telling
us which year we are in over a series of years.
The solar year is 365.24 days in length, and each lunation is on average 29.5 days. If the months were determined by the moon and used in conjunction with the sun, every so many solar years would include the start of a 13th lunar month. The Bible, however, only speaks of 12 months in a year; there is never a mention of a 13th month. So it appears to me that the 12 months mentioned in the Bible are not “lunar months”.
Also, a year is a repeat of something and since it is often used to measure the length of days of a man’s life, I would expect it to be relatively equal in length from year to year. Therefore, I don’t see how the moon can be a determining factor for each month of the year since there could be a variation of up to 30 days from one year to the next when
doing so.
As for looking to the produce of the land for the determination of the year, it seems to me that the produce *bears witness* to the start of the year as a *second* witness; it is not the determining factor. Rather, the lights in the sky are the determining factors since the Bible says they are “for signs for seasons for days and years”.
I have often thought that the start of the year is solely based on the spring equinox, but now I’m thinking there may be a certain amount of wiggle room there. The Book of Enoch claims that a solar year is 364 days precisely with 4 of those days “not counted”; those 4 days are intercalary marking the end of one season quarter and the start of another. This would help explain why the Bible seems to speak of only 360 days in a year or 12 months/year at 30 days each.
364 is evenly divisible by seven, producing exactly 52 weeks in a year. The tabernacle / temple system speaks of offerings being made on the 7th days (Sabbaths), with the rotation of priests being every two weeks (I think) 24 weeks: one priest serving per week at a time. Given this it seems to me that there is an unbroken 7-day cycle.
I believe the first Sabbath day of the year falls first year fell on “the third day” of the year given what I’ve studied in the Bible regarding all the dates addressed in it.
If “Saturday” is the 7th day of the unbroken 7-day cycle, my best educated guess (and its only a guess) is that the first day of the year always falls on the first year fell on the “Thursday” immediately after the spring equinox.
If there is a need to keep the years in sync with the seasons, having the first season always be spring, then this would require an intercalary “week” every so many years to keep the
start of the year from falling back in the seasons over the course of many years.
Of all that I have considered over the past so many years, this conclusion makes the most sense to me, and I don’t see anything in Scripture to refute it. Do you? If so, please do share it with me.
But if there is no need to keep the years in sync with the seasons like that, then it appears to me that the 364-day year repeats without interruption and the start of the year falls back in the seasons of winter, fall, summer and spring over the course of many years.
Many of my notes on my calendar findings can be found here if you want to see why I have drawn the conclusions that I have:
http://messyanic.com/the-road-were-on/my-calendar-journey/calendar-notes/
As always, I encourage all to prayerfully study these things out for themselves. I recognize that I can be in error, and I’m open to correction. 😉
Thanks for writing me. It felt good for me to lay all this out for my own benefit; I hope it was helpful to you. I look forward to hearing what you think after further investigation.
Shalom,
Carrie
