The entire month of December, along with a couple of weeks in November and January, have been viewed since antiquity by numerous cultures globally to represent the "birth of light" in some fashion or another. This focus on December 21st or 22nd represents pendantry based on a lack of knowledge about the numerous light festivals.
Please see the page from my 2010 Astrotheology Calendar
As has been pointed out, December 25th was struck upon because the sun was perceived not to move for three days before it begins its northerly approach - all from a geocentric perspective, of course. Hence, if the sun stops moving at midnight on December 21st, three days later, at midnight on December 24th, it is "born again" or "resurrected." It's that simple, and that's the reason why we have this date.
In any event, as we can see from the above, winter solstice festivals have been held on many days during the winter months. In India, the winter solstice or Makar Sankrati
is still celebrated around January 13-15th. In previous eras, January 5th, 6th and 7th were solstice days, which is why the Eastern Orthodox Church continues to celebrate Jesus's birth on January 6th
. This same day was celebrated in Egypt as one of Osiris's birthdays as well.
We will continue to discuss "December 25th" as the winter solstice, as well as to employ the perfectly useful word "temple" when describing buildings from antiquity that likely were constructed for religious purposes.
Why suffer from Egyptoparallelophobia, when you can read Christ in Egypt
? Try it - you'll like it: