Jesus' date of birth
Luk_1:5-13
In the time of Herod king of Judea there was a priest named Zechariah, who belonged to the priestly division of Abijah; his wife Elizabeth was also a descendant of Aaron. Both of them were upright in the sight of God, observing all the Lord's commandments and regulations blamelessly. But they had no children, because Elizabeth was barren; and they were both well on in years. Once when Zechariah's division was on duty and he was serving as priest before God, he was chosen by lot, according to the custom of the priesthood, to go into the temple of the Lord and burn incense. And when the time for the burning of incense came, all the assembled worshippers were praying outside. Then an angel of the Lord appeared to him, standing at the right side of the altar of incense. When Zechariah saw him, he was startled and was gripped with fear. But the angel said to him: "Do not be afraid, Zechariah; your prayer 32 has been heard. Your wife Elizabeth will bear you a son, and you are to give him the name John.
Luk_1:23-24
When his time of service was completed, he returned home. After this his wife Elizabeth became pregnant and for five months remained in seclusion.
Luk_1:26-31
In the sixth month, God sent the angel Gabriel to Nazareth, a town in Galilee, to a virgin pledged to be married to a man named Joseph, a descendant of David. The virgin's name was Mary. The angel went to her and said, "Greetings, you who are highly favoured! The Lord is with you." Mary was greatly troubled at his words and wondered what kind of greeting this might be. But the angel said to her, "Do not be afraid, Mary, you have found favour with God. You will be with child and give birth to a son, and you are to give him the name Jesus.
Luk_1:32-36
He will be great and will be called the Son of the Most High. The Lord God will give him the throne of his father David, and he will reign over the house of Jacob for ever; his kingdom will never end."
"How will this be," Mary asked the angel, "since I am a virgin?" The angel answered, "The Holy Spirit will come upon you, and the power of the Most High will overshadow you. So the holy one to be born will be called the Son of God. Even Elizabeth your relative is going to have a child in her old age, and she who was said to be barren is in her sixth month.
1Ch_24:3
With the help of Zadok a descendant of Eleazar and Ahimelech a descendant of Ithamar, David separated them into divisions for their appointed order of ministering.
1Ch_24:7-19
The first lot fell to Jehoiarib, the second to Jedaiah,
the third to Harim, the fourth to Seorim,
the fifth to Malkijah, the sixth to Mijamin,
the seventh to Hakkoz, the eighth to Abijah,
the ninth to Jeshua, the tenth to Shecaniah,
the eleventh to Eliashib, the twelfth to Jakim,
the thirteenth to Huppah, the fourteenth to Jeshebeab,
the fifteenth to Bilgah, the sixteenth to Immer,
the seventeenth to Hezir, the eighteenth to Happizzez,
the nineteenth to Pethahiah, the twentieth to Jehezkel,
the twenty-first to Jakin, the twenty-second to Gamul,
the twenty-third to Delaiah and the twenty-fourth to Maaziah.
This was their appointed order of ministering when they entered the temple of the LORD, according to the regulations prescribed for them by their forefather Aaron, as the LORD, the God of Israel, had commanded him.
The descendants of Abijah, which included Zechariah, got the 8. lot for their temple ministering. This means, they where on duty during the 4. Month (Tammuz). Six month later (Elisabeth was in her sixth month), the angel Gabriel came to Mary, and she got pregnant. Jesus was born 9 month later of course, which means in the month of Tishri, the seventh month. Tabernacle is appointed for the days between the 15. - 21 Tishri. Therefore, Jesus was borne around the feast of Tabernacle.
Source unknown
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