For centuries, Christians have celebrated the birth of Jesus on December 25th. Conventional wisdom holds that it supplanted the pagan festivals that marked the Winter Solstice.
"The ancient Egyptians, they were already celebrating the pagan holidays," says David Silverman, president of American Atheists.
"Saturnalias was always celebrated on December 25th. And it was celebrated with trees and gifts and songs and roasting chestnuts on an open fire. Christians came and in an effort to grow Christianity, they simply usurped those religions and they call it their own."
But some scholars disagree.
"The Romans used to celebrate a pagan deity, and they changed the celebration to the Christian God which I think the Romans had a right to do,” said Paul Vischer, creator of The Veggie Tales, a Christian video series for children.
“I don't think Christians stole it."
Christian theology professor Gregg Allison agrees, but for different reasons. "The early church certainly in the third or fourth centuries was not at all receptive to pagan practices,” he says. “In fact, the early church in this time denounced any association with paganism and pagan festival. So I don't think that theory is very plausible."
No one knows for certain when Jesus was born, and many dates have been batted around.
The early church focused on Jesus' crucifixion and resurrection as the defining moment of Christian faith. Later it was decided to celebrate his birth to show the Divine Son of God's humanity. But then the challenge was to figure out a date.
"Now here is the move that the early church made," says Allison. "It believed that Jesus was conceived on the same day that he was crucified. So the belief was that he was conceived on the 14th or 15th of Nisan, according to the Hebrew calendar; translated, he was conceived on March 25th on the Roman calendar. Fast forward nine months and we have the date of December 25th."
Allison asserts that "It was important for biblical reasons as well as theological reasons for the church to celebrate the birthday of Jesus Christ." It was to celebrate that the Son of God did really become a human being and that that God Man was Jesus of Nazareth.
So the date is a settled tradition, if not a confirmed fact.
What is certain is that Christmas has become commercialized, that Jesus’ birth has become a sidebar to the main event of shopping and gift giving. It is far from what the early church fathers intended.
Whether it was on December 25th or some other day ... the fact is: Jesus was born. And for 2000 years, Christians have celebrated.
Lauren Green currently serves as Fox News Channel's (FNC) chief religion correspondent based in the New York bureau. She joined FNC in 1996. Her new book is "Lighthouse Faith: God as a Living Reality in a World Immersed in Fog."