One December afternoon, before he outgrew every shoe in the house, my son and I went to the woods to cut a Christmas tree. He was old enough by then to navigate the snow the same way I did when I was a boy hunting blue spruces, which are pretty elusive in southern Maine.

We hiked up the hill behind the house through floating snowflakes with an ax and great expectations. We examined small hemlocks and pines, and ragged black spruces. Some white spruces were the right height and had fuller needles but might have smelled skunky in the house. We saw a lot of sparsely equipped young firs. Our boots crunched snow for a long time.

In my boyhood, the woods had the reverent air of a cathedral. At Christmastime the church pageant, colored lights and the likelihood of Santa angling his sleigh through the treetops in the middle of the night blazed in my mind. The balsams and spruces were like a place where houses are all churches and have spires.

Commercially we call it “magic,” though there might be a better word for the depths that underlie the advertising. Christmastime is even older than Christ.

For Christ (the scholars tell us) was probably born in the spring, not December. But long before his time, rituals of rebirth and renewal were celebrated at the winter solstice, the day in late December when the noon sun stops being lower each day, and begins getting higher. To ancient people, this was a powerful cosmic moment. The sky and its workings were expressions of activity in the divine world, and the motion of the sun lowering in the sky from June to December, and then rising from December to June, was seen as a living, awesome sign of the power that drives the universe. They reverenced the sun’s rebirth, and used evergreens as ritual symbols because their needles, like the sun, survive and live again.

The profundity of this is hard to grasp here in the scientific age. As far as we know, we’ve outgrown childish superstitions about supernatural powers and our wise men understand that physics and biochemistry explain virtually everything.

As it happens, the pagan reverence of the solstice never really disappeared. During the A.D. 300s, the emperor Constantine and the church fathers linked Christ to the renewal celebrations by appointing Dec. 25 as his birthday. Christ, after all, is the personification of rebirth. We still use evergreens to remind ourselves that something awesome is happening just the other side of the sun.

On our tree hunt, I was hoping Jack would catch the drift of this, but he was getting tired. So we cut the fullest-branched fir we could find and dragged it home in the snow.

Things are almost always larger in imagination than in the living room. The tree turned out to be a scraggly, Charlie Brown-style skeleton. We hung our ornaments and lights on it anyway, much to the shock of a delivery man who caught a glimpse of it, dropped his jaw, and scrammed to his truck.

Still, following in the footsteps of his wandering dad, Jack tells me he remembers that expedition, and the Christmas woods remain more real in his mind than all the scientifically grown and nurtured trees we’ve bought since.