Sol Invictus

[Imperial Dave]

https://open.substack.com/pub/mythandmystery/p/sol-invictus-7cb?utm_source=share&utm_medium=android&r=4t2zpe

Hopefully of interest

[Jim Webster]

One problem  is that we are used to everybody using the same calendar which is synchronised around the world.
In the ancient world, especially around the Med, this wasn't true. A lot of Greek cities had their own calendars, with their own dating system. Others were using the Seleucid era, a Parthian era, a Roman system which wasn't particularly useful, and dating by the Olympic games.

Luke 3 starts with a nice example of what you had to do if you wanted to make sure people over a wide area knew what date you were talking about.

"In the fifteenth year of the reign of Tiberius Caesar—when Pontius Pilate was governor of Judea, Herod tetrarch of Galilee, his brother Philip tetrarch of Iturea and Traconitis, and Lysanias tetrarch of Abilene—  during the high-priesthood of Annas and Caiaphas, the word of God came to John son of Zechariah in the wilderness. "

Another issue is the actual date. The same day might have different names in Antioch, Jerusalem, and Damascus. For most people it doesn't matter, for official business you just tell them the date on the Roman calendar and it's their job to work out when that is. But if you're running a religion and want everybody to hold a feast day at the same time, rather than having to work out a score of calendars, you just use astronomy.

A nice complicated example of how you do this is Easter (which, to quote wiki, Easter is celebrated on the first Sunday after the Paschal full moon (a mathematical approximation of the first astronomical full moon, on or after 21 March – itself a fixed approximation of the March equinox). Determining this date in advance requires a correlation between the lunar months and the solar year, while also accounting for the month, date, and weekday of the Julian or Gregorian calendar. (complicated because it's linked to Passover in the Jewish calendar)

But the easy way to fix dates is to link them to solstices or equinoxes. It saves a lot of complicated calculation. But this is why a lot of religious festivals congregate around 21st December

[Nick Harbud]

This reminds me of my RE teacher explaining to the class how Jesus was born in 5 BC... 

[Imperial Dave]

We had the same teacher...