Q: A friend says her church doesn't celebrate Christmas because it began as a pagan holiday. Why then do most churches celebrate Christmas?

—Brian Smith, via the Internet.

A: Was the event we now call Christmas originally a "pagan holiday"? In some ways. Does that mean the church should discard it, along with its lights, tinsel, and increasing commercialism? Only if we are prepared to abandon many other holidays and common Christian practices that the early church co-opted for its own purpose of glorifying Christ.

Christmas has its origins in the fourth century. December 25, which Christians now herald as Jesus' birthday, was actually the date on which the Romans celebrated the birth of the sun god.

After the Roman emperor Constantine converted to Christianity at the Milvian Bridge in 312, he sought to combine the worship of the sun god with worship of Christ. Christian leaders accepted Constantine's conversion in a positive light and saw the "Christ-mass" celebration as a vital part of the process of converting the pagan world.

Long before Constantine, Christians found ways to redeem local cultures and salvage elements in those cultures that naturally pointed to Christ, whether Hebrew, Syrian, Greek, or Roman. They denounced inhumane pagan practices, but at the same time took over pagan temples and converted them to churches. They replaced the old gods in popular devotion with heroic martyrs of the persecutions. And they replaced the holy days of paganism with festivals of the Christian year.

Larger questions loom behind the observance of Christmas: Why a church calendar at all? Why a Sunday? Why an Easter? Is there New Testament authority for religious holidays?

As Christmas, Easter, and Sunday all indicate, the Christian calendar is based upon the major events of the New Testament. Early Christians shared a conviction that believers need regular reminders of the great events of redemptive history. Didn't Jesus himself endorse the practice when he instituted the Lord's Supper? "This do in remembrance of me."

Besides, our celebration of Christmas or any other Christian "holy day" goes much deeper than the date on which we observe it. The first Christmas celebration did not commemorate a date at all but a supremely important event—the appearance of Israel's promised Messiah and Lord of the Nations.

Early Christians did not know the specific night the angels sang or the baby cried any more than we do. A few believers tried to calculate the date, but most of these indulged in all sorts of speculations and differed with each other. As a result, down to the first half of the fourth century the churches attached no greater significance to December 25 than to many other dates.

This much we know: Before there was December 25, there was January 6. As early as the second century, Christians celebrated Jesus' appearance at the Jordan and his baptism by John on January 6. Some time later they expanded this festival to include Christ's appearance at birth. Christians called it Epiphany, or manifestation. So the meaning of the first Christmas was not pagan; it was a celebration of the Word manifest in flesh.

It is important to note that the link between Christ and Constantine's sun god was light. For generations, Christians had been singing about Christ's appearance as the true Light, as the light of Creation and redemption. Christians in these early centuries were fascinated by the image of light breaking into our darkness. "We have seen a sign from heaven, the shining star," the choir sings in one early liturgy. Another hymn announces:

The whole creation proclaims,
The Magi proclaim,
The star proclaims:
Behold! the king's son is here!

This impulse to sing the praises of Christ's birth did not come from paganism. It was a result of Christians reflecting on the fact that God became man in Jesus Christ and condescended to our lowly estate.

Many in the fourth-century church viewed Constantine's conversion as the fulfillment of Malachi's prophecy: In the day of the Lord, the "Sun of Righteousness will arise with healing in his wings" for those who fear the Lord's name (4:2).

In a Christmas sermon, Bishop Ambrose in Milan spoke for many Christians of that day when he said, "Well do Christian people call this holy day, on which our Lord was born, the day of the new sun; and they assert it so insistently that even Jews and pagans agree with them in using that name for it. We are happy to accept and maintain this view, because with the day spring of the Savior, not only is the salvation of man kind renewed, but also the splendor of the sun. … For if the sun withdrew its light when Christ suffered, it must shine at his birth with greater splendor than ever before."

Bruce L. Shelley is senior professor of church history at Denver Seminary.

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