In the dead of winter, pine trees and fire stand out as bold signs of rebellion against the cold dead surroundings. All other trees are dead. All other existence is cold. The tree and the fire are like lifelines to nature. Imagine winter without any warmth or alive trees whatsoever. The Yule tree and the burning Yule log are eternal symbols of life and energy that survive the winter. That is why they are holy. They are something a pagan can have faith in. The ancients were after-all even less certain than we are today that the Sun would rise tomorrow, that the warm days would return, that green spring would come again. They had to have faith in the message nature sent them through the examples of fire and alpine trees. The very act of bringing an alpine tree inside can then obviously be seen as an attempt to save greenery from the distress of the cold outside. We were trying to keep the greenery alive by keeping it warmer inside. And with astronomical precision we started a huge bonfire with fire passed down from the previous year on the night when the Sun was most lost to us. This being an obvious attempt to ensure we didn’t lose all flame and fire in the dead of winter. There is very little mystery behind these practices when you put yourself into the shoes of our ancient ancestors and think about the conditions they were dealing with.