Joh 1:14 And the Word became flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth.
Gal 4:4a but when the appointed time came, God sent forth his Son.
There were two priestly courses in a year (sometimes three). Most calculations for Yeshua's birth, based on those courses, fall in the Hebrew months of Aviv / Nissan (March / April) and Tishri (September / October).
That is why many believe that Yeshua was born during Passover or Sukkot (Feast of Tabernacles).
There are several reasons why it could not be in the month of Tishri:
It was too late in the year:
The wise men would not have travelled in the middle of winter (Their visit was more than 40 days after his birth, because he first was dedicated as the first-born in the Temple),
The sheep would no longer be in the field,
Herod would not be in Jerusalem, but in his winter palace in Jericho,
It was after the appearance of the Star of Bethlehem,
It would have been long after the census of Quirinius (Luk 2:2),
It does not fit with the theme of the appointed time (Yeshua first had to become flesh before he could die as the Pasgalam), and
It would mean that Joseph deliberately waited until near the end of Miriam's pregnancy before embarking on the journey to Bethlehem (something that would obviously be ridiculous).
The end date of Zechariah's priesthood service (Luke 1: 5) was January 25, 3 BC (Abijah's division). It was on the 8th of the month Shevat according to the Hebrew calendar (Biblical dates are almost always based on the Hebrew calendar). He went home and his wife Elizabeth falls pregnant.
She went into seclusion for five months (Luke 1:24). That brings us to 8 Tammuz / 22 June 3 BC.
The next day (9 Tammuz / June 23, 3 BC, the first day of the 6th month of Elizabeth's pregnancy) the angel Gabriel visited Mary.
He told her that she would give birth to the Messiah, and she became pregnant (Luke 1: 26-35). Miriam immediately went to visit Elizabeth (Luke 1:39). She was already pregnant when Elizabeth greeted her (Luke 1:41).
According to Epiphanius, Miriam's pregnancy was "ten months minus fourteen days and eight hours". It is apparently based on the apocryphal book "Wisdom of Solomon" (Wisdom 7: 2).
Epiphanius was a Greek monk from Egypt and would have used Egyptian months (as Clement did). Egyptian months have 30 days.
Days of pregnancy: 10 x 30 – 14 = 286
Birth 286 days after 9 Tammuz / 23 June 3 BC brings us to 1 Aviv / 5 April 2 BC.
1 Aviv: A very meaningful appointed time
1 Aviv is the first day of the Hebrew religious year. It is also on a new moon. Therefore it is, according to the Bible, one of the appointed times.
1 Aiv is a very significant date. On this date:
The Tabernacle was set up (Exo 40:17),
The priestly service started (Exo 40:12-15),
The regnal years for Jewish kings are calculated.
The theme and meaning of this date confirm who and what Yeshua is:
He came to live among us,
He is the Eternal High Priest according to the Order of Melchizedek,
He was born as the King of the Jews.
Yeshua first had to become flesh before he could die as the Passover Lamb. The Biblical year is calculated from 1 Aviv, so all other designated times are calculated accordingly.
Everything starts with Yeshua.
(A full description of this article with references can be read in Gerhard Groenewald's book "The Star Messengers - Proclaimers of times and signs".)
Image: Gerhard Groenewald combined a Torah scroll (by Katie Chao, flickr) and a nativity scene (Grace Fox, flickr). https://creativecommons.org/licenses/by-sa/2.0/