If Christians are correct about what happened on that first Christmas day it's an event of such magnitude as to be incomprehensible. If what the Gospel writers tell us is true then the child who was born in a stable that day was not just a special baby, it was the incarnation, the incorporation, of the very creator of the universe!
This is such a breathtaking thought that it's humanly impossible to get one's mind around it. The God who created us and all the galaxies in the cosmos deigned to make Himself like one of us in order to share in the pains and sorrows of being human, being willing ultimately to suffer an excruciating death, all so that our death need not be the end of our existence.
This is what the Gospel narratives insist actually, literally happened, and if they're correct, if they're only approximately true, they surely recount the greatest, most astonishing, story ever told.
This three minute video beautifully illustrates the point:
As we go about making our Christmas preparations this year, it'd be good to keep in our minds the literal wonder of what it is we're preparing to celebrate.