A Note on Dates

Okay, I know I set myself a goal of posting every day during Advent, and haven’t done so for weeks.  But in my defence, the date of Christmas (and therefore of Advent) is highly ambiguous.  Still, let’s start with a carol:

 

Rejoice and be merry in songs and in mirth,
O praise our Redeemer, all mortals on Earth,
For this is the birthday of Jesus our King,
Who brought us salvation; his praises we’ll sing!

 

So says the carol.  But of course, we know Christmas isn’t really Jesus’s birthday, right?  After all, the Church just decided to make 25^th December the date for celebrating the birth of Christ because it was already the date of a popular Roman holiday.  (Well, mostly that – it was also that someone decided that for a perfect life, someone would die on the same day that they were conceived, and we know Jesus died in spring, so – let’s say he was born in the winter.)

 

Still, does the Bible give us any clues as to when Jesus really was born?  Well, some people, such as William Struse in his blog The Thirteenth Enumeration argue that he was probably born in the autumn, at Sukkot, the Feast of Tabernacles.  After all, the poetic description of the Incarnation in John’s gospel, ‘The Word became flesh and made his dwelling among us,’ is more literally translated ‘And the Word became flesh, and did tabernacle among us’.  John might have chosen this word because he knew that Jesus was born at Sukkot. 

 

But if Jesus was not merely born in a stable but born at a time when everyone was camping out in shelters made of tree branches anyway, why would Luke have written that Jesus was laid in a manger ‘because there was no guest room available for them,’  as if this was a great hardship and indignity for Jesus and his family to bear?  (Yes, I know traditional versions say ‘Because there was no room for them at the inn,’ but Bethlehem in reality was a tiny village which is unlikely to have had an inn – probably Mary and Joseph had expected to stay with family who lived there, but the spare room was full of other visiting relatives.) 

 

Struse argues that the reason there was so much crowding was that Jesus was born at Sukkot, which along with Pesach (Passover) and Shavuot (the Festival of Weeks, celebrated 7 weeks after Passover) was one of the Three Pilgrimage Festivals in which all Israelites made a pilgrimage to Jerusalem.  But this was in Bethlehem, seven miles from Jerusalem (admittedly not a hugely long walk, but surely in a camping festival, people would be more likely to build shelters nearer to the city?), and Luke’s explanation for Mary and Joseph being in Jerusalem was that the Roman authorities had ordered everyone to go to the town their families came from to register for a census.

 

Still, can we at least estimate the approximate time of year when Jesus was born?  According to Luke’s gospel, Mary became pregnant with Jesus when her cousin Elizabeth was in the sixth month of her own pregnancy with her son John.

 

 Elizabeth’s husband, Zechariah, was a priest in the Abijah section of the priesthood, who were the eighth of the twenty-four divisions of priests who served over the course of a year.  Luke’s gospel tells us that while Zechariah was offering incense in the Temple, an angel appeared to him and told him that he was going to become a father.  When Zechariah finished his term of duty, he went home, he and Elizabeth made love and she became pregnant.

 

The Jewish year starts in spring with the month of Nisan, which roughly corresponds to April in our calendar, the Gregorian calendar.  The Jewish religious year, like the Muslim one, uses actual lunar months, instead of inventing ‘calendar months’ which bear no resemblance to the actual position of the moon.  However, whereas the Muslim calendar treats a year of consisting of 12 lunar months of 29-30 days, so that the calendar year is 10 days shorter than the actual year, the Jewish calendar adds a leap month every few years, so that the religious year doesn’t get too out of sync with the actual time of year for being useful in remembering when to plant crops and harvest.

 

So, Nisan starts somewhere from 12^th March to 11^th April, and finishes somewhere from 10^th April to 10^th May.  If Zechariah was on duty for the latter half of the month of Tammuz, he finished his course of duty somewhere between 7^th July and 6^th August.  We don’t know how soon after this John was conceived, but let’s suppose that it was just a few days later – say, 11th July – 10th August.

 

Mary became pregnant ‘in the sixth month’ of that pregnancy, so Elizabeth was somewhere between five months pregnant and nearly six months pregnant.  So, still using the lunar calendar, this was 148 - 177 days after John’s conception, somewhere between 6^th December and 4^th February.

 

Now, although everyone ‘knows’ that pregnancy takes nine months, this is counting from the mother’s last period before she became pregnant.  In practice, human pregnancy usually lasts 37-38 weeks after fertilisation, or 36-37 weeks after the embryo implants in the womb.  So if Mary’s pregnancy lasted 259-266 days, then Jesus was probably born somewhere between 22nd August and 28th October. 

 

Sukkot takes place from the 15th to 21st day of Tishrei in the Jewish calendar.  In terms of our calendar, the start date of Sukkot would be somewhere from 19th September to 19th October, and the end date somewhere 25th September to 25th October).  So this fits.

 

However, we don’t know for certain that priestly divisions worked for half a month once a year, instead of for a week twice a year.  For all we know, Zechariah could have been on duty for the final week of Iyar (end date 9th May - 8th June) and again in the final week of Cheshvan (end date 3rd November to 2nd December) and John was conceived after one of these.  In this case, Jesus would have been born either between 24th June and 28th August, or between 18th December and 22nd February.  So in this case, 25th December possibly really is Jesus’s birthday – but so is more than half the year!  This table lays out the possible dates:

 

	Abijah’s course on duty	Abijah’s course ends duty (in Gregorian calendar)	Elizabeth conceives	Mary conceives in 6th month of Elizabeth’s pregnancy = 148 - 177 days after this	Length of Mary’s pregnancy	Jesus born
If course served half a month at a time	2nd half of Tammuz	7th July to 6th August	11th July – 10th August	6th December – 4th  February	259-266 days	22nd August – 28th October
If course served for 1 week, twice a year	Final week of Iyar	9th May to 8th June	13th May – 12th June	8th October – 6th December	259-266 days	24th June- 28th August
	Final week of Cheshvan	3rd November to 2nd December	7th November – 6th December	3rd April – 1st June	259-266 days	18th December – 22nd February

 

Many people say that of these possible seasons for Jesus to be born in, summer, autumn or winter, winter is the least likely, considering that the shepherds and their sheep stayed outside all night.  But winter in Bethlehem isn’t all that cold – the forecast for this week predicts temperatures of around 16 to 28 Centigrade by day, and around 10 to 16 Centigrade by night.  They’re getting a lot of rain and thunder, admittedly, but it certainly isn’t ‘In the Bleak Midwinter’.  In terms of temperature, being outdoors in a Bethlehem December would be similar to a British person’s experience of going camping in April or May. In terms of rain, it would be like a British person’s experience of going camping in August or September.

 

So I’m (possibly) going to stop complaining about people who put up Christmas decorations way too early, or Australians holding Yulefest celebrations in July in addition to the summer Christmas in December.  And I’m going to feel that there is an extra reason for celebrating Lammas and autumn harvest festivals.  After all, either of these could be Christmas, for all we know.

 

More importantly, I ought to learn to control my temper better and extend peace and goodwill to all people.  As ‘O Little Town of Bethlehem’ concludes, ‘O Holy Child of Bethlehem, descend to us, we pray.  Cast out our sin, and enter in; be born in us today.’