The Days are Getting Longer

Earlier cultures were very aware of the passing of the seasons,
the phases of the moon and the angle of the sun in the sky.

They noticed that the sun (which they thought of as a god)
appeared lower in the sky each day as December 21st
approached and they thought of it as "dying". On the 21st
the sun was at it lowest point in the sky and day to day
changes in the sun's position of was barely noticeable.

They thought of the sun as dead.

But after about 3 days or so a small increase in the sun's height
above the horizon was noticeable and the sun, they thought,
was reborn.

Such an interesting story those poor uninformed ancient pagans
had. That is, the idea that their god had died only to rise from
the dead three days later on about December 24th. Yeah, born
again around Christmas. Perhaps parts of the story were
compelling enough to be incorporated in to more "modern"
belief systems?