why do we celebrate Jesus birthday on Dec 25th

Why do we celebrate Jesus birthday on Dec 25th, when it is not know exactly when he was born.

The early Christian community distinguished between the identification of the date of Jesus' birth and the liturgical celebration of that event. The actual observance of the day of Jesus' birth was long in coming. In particular, during the first two centuries of Christianity there was strong opposition to recognizing birthdays of martyrs or, for that matter, of Jesus. Numerous church fathers offered sarcastic comments about the pagan custom of celebrating birthdays when, in fact, saints and martyrs should be honoured on the days of their martyrdom?-their true "birthdays," from the church's perspective.

The precise origin of assigning December 25 as the birth date of Jesus is unclear. The New Testament provides no clues in this regard. December 25 was first identified as the date of Jesus' birth by Sextus Julius Africanus in 221 and later became the universally accepted date. One widespread explanation of the origin of this date is that December 25 was the Christianizing of the dies solis invicti nati ("day of the birth of the unconquered sun"), a popular holiday in the Roman Empire that celebrated the winter solstice as a symbol of the resurgence of the sun, the casting away of winter and the heralding of the rebirth of spring and summer. Indeed, after December 25 had become widely accepted as the date of Jesus' birth, Christian writers frequently made the connection between the rebirth of the sun and the birth of the Son. One of the difficulties with this view is that it suggests a nonchalant willingness on the part of the Christian church to appropriate a pagan festival when the early church was so intent on distinguishing itself categorically from pagan beliefs and practices.

A second view suggests that December 25 became the date of Jesus' birth by a priori reasoning that identified the spring equinox as the date of the creation of the world and the fourth day of creation, when the light was created, as the day of Jesus' conception (i.e., March 25). December 25, nine months later, then became the date of Jesus' birth. For a long time the celebration of Jesus' birth was observed in conjunction with his baptism, celebrated January 6.

Christmas began to be widely celebrated with a specific liturgy in the 9th century but did not attain the liturgical importance of either Good Friday or Easter, the other two major Christian holidays. Roman Catholic churches celebrate the first Christmas mass at midnight, and Protestant churches have increasingly held Christmas candlelight services late on the evening of December 24. A special service of "lessons and carols" intertwines Christmas carols with Scripture readings narrating salvation history from the Fall in the Garden of Eden to the coming of Christ. The service, inaugurated by E.W. Benson and adopted at the University of Cambridge, has become widely popular.

None of the contemporary Christmas customs have their origin in theological or liturgical affirmations, and most are of fairly recent date. The Renaissance humanist Sebastian Brant recorded, in Das Narrenschiff (1494; The Ship of Fools), the custom of placing branches of fir trees in houses. Even though there is some uncertainty about the precise date and origin of the tradition of the Christmas tree, it appears that fir trees decorated with apples were first known in Strasbourg in 1605. The first use of candles on such trees is recorded by a Silesian duchess in 1611. The Advent wreath?-made of fir branches, with four candles denoting the four Sundays of the Advent season?-is of even more recent origin, especially in North America. The custom, which began in the 19th century but had roots in the 16th, originally involved a fir wreath with 24 candles (the 24 days before Christmas, starting December 1), but the awkwardness of having so many candles on the wreath reduced the number to four. An analogous custom is the Advent calendar, which provides 24 openings, one to be opened each day beginning December 1. According to tradition, the calendar was created in the 19th century by a Munich housewife who tired of having to answer endlessly when Christmas would come. The first commercial calendars were printed in Germany in 1851. The intense preparation for Christmas that is part of the commercialization of the holiday has blurred the traditional liturgical distinction between Advent and the Christmas season, as can be seen by the placement of Christmas trees in sanctuaries well before December 25.
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In most European countries gifts are exchanged on Christmas Eve, December 24, in keeping with the notion that the baby Jesus was born on the night of the 24th. ... ... ...

It is unknown exactly when or why December 25 became associated with Christ's birth. The New Testament does not give a specific date.[14] Tertullian does not mention it as a major feast day in the Church of Roman Africa. In 245, the theologian Origen denounced the idea of celebrating Christ's birthday "as if he were a king pharaoh". He contended that only sinners, not saints, celebrated their birthdays.[15]Sextus Julius Africanus popularized the idea that Christ was born on December 25 in his Chronographiai, a reference book for Christians written in AD 221.[11] This date is nine months after the traditional date of the Incarnation (March 25), now celebrated as the Feast of the Annunciation. March 25 was considered to be the date of the vernal equinox and therefore the creation of Adam; early Christians believed this was also the date Christ was crucified. The Christian idea that Christ was conceived on the same date that he died on the cross is consistent with a Jewish belief that a prophet lived an integral number of years.[16] Thus, the date as a birthdate for Christ is traditional, and is not considered to be his actual date of birth.

Although the identification of the birth date of Christ is debated, liturgical celebrations of the Nativity were celebrated from at least A.D. 200 in the Christian East. The earliest reference is found in St. Clement of Alexandria's writings in reference to a celebration of the Nativity and the Epiphany. [17] Another reference is found in the Chronography of 354, an illuminated manuscript compiled in Rome in 354.[1][18] In the East, early Christians celebrated the birth of Christ as part of Epiphany (January 6), although this festival focused on the baptism of Jesus.[19]

Christmas was promoted in the Christian East as part of the revival of Catholicism following the death of the pro-Arian Emperor Valens at the Battle of Adrianople in 378. The feast was introduced to Constantinople in 379, and to Antioch in about 380. The feast disappeared after Gregory of Nazianzus resigned as bishop in 381, although it was reintroduced by John Chrysostom in about 400.[1] The Twelve Days of Christmas are the twelve days from Christmas Day to the Feast of Epiphany on January 6 that encompass the major feasts surrounding the birth of Christ. In the Latin Rite, one week after Christmas Day January 1 has traditionally been the celebration the Feast of the Naming and Circumcision of Christ, but since Vatican II, this feast has been celebrated as the Solemnity of Mary, Mother of God.

In the Roman calendar, the Saturnalia was designated a holy day, or holiday, on which religious rites were performed. Saturn, himself, was identified with Kronos, and sacrificed to according to Greek ritual, with the head uncovered. The Temple of Saturn, the oldest temple recorded by the pontiffs, had been dedicated on the Saturnalia, and the woolen bonds which fettered the feet of the ivory cult statue within were loosened on that day to symbolize the liberation of the god.

It also was a festival day. After sacrifice at the temple, there was a public banquet, which Livy says was introduced in 217 BC (there also may have been a lectisternium, a banquet for the god in which its image is placed in attendance, as if a guest). Afterwards, according to Macrobius (I.10.18), the celebrants shouted "Io, Saturnalia!" at a riotous feast in the temple.

The Saturnalia was the most popular holiday of the Roman year. Catullus (XIV) describes it as "the best of days," and Seneca complains that the "whole mob has let itself go in pleasures" (Epistles, XVIII.3). Pliny the Younger writes that he retired to his room while the rest of the household celebrated (Epistles, II.17.24). It was an occasion for celebration, visits to friends, and the presentation of gifts, particularly wax candles (cerei), perhaps to signify the returning light after the solstice, and sigillaria. Martial wrote Xenia and Apophoreta for the Saturnalia. Both were published in December and intended to accompany the "guest gifts" which were given at that time of year. Aulus Gellius relates in his Attic Nights (XVIII.2) that he and his Roman compatriots would gather at the baths in Athens, where they were studying, and pose difficult questions to one another on the ancient poets, a crown of laurel being dedicated to Saturn if no-one could answer them.

During the holiday, restrictions were relaxed and the social order inverted. Gambling was allowed in public. Slaves were permitted to use dice and did not have to work. Instead of the toga, less formal dinner clothes (synthesis) were permitted, as was the pileus, a felt cap normally worn by the manumitted slave that symbolized the freedom of the season. Within the family, a Lord of Misrule was chosen. Slaves were treated as equals, allowed to wear their masters' clothing, and be waited on at meal time in remembrance of an earlier golden age thought to have been ushered in by the god. In the Saturnalia, Lucian relates that "During My week the serious is barred; no business allowed. Drinking, noise and games and dice, appointing of kings and feasting of slaves, singing naked, clapping of frenzied hands, an occasional ducking of corked faces in icy water?-such are the functions over which I preside."

This equality was temporary, of course; and Petronius speaks of an impudent slave being asked at some other time of the year whether it was December yet. Dio writes of Aulus Plautius, who was to lead the conquest of Britain, cajoling his troops. But they hesitated, "indignant at the thought of carrying on a campaign outside the limits of the known world." Only when they were entreated by a former slave dispatched by Claudius did they relent, shouting "Io, Saturnalia" (LX.19.3).

(If a time of merriment, the season also was an occasion for murder. The Catiline conspirators intended to fire the city and kill the senate on the Saturnalia, when many would be preoccupied with the festivities. Caracalla plotted to murder his brother then, and Commodus was strangled in his bath on New Year's eve.)

At the end of the first century AD, Statius still could proclaim: "For how many years shall this festival abide! Never shall age destroy so holy a day! While the hills of Latium remain and father Tiber, while thy Rome stands and the Capitol thou hast restored to the world, it shall continue" (Silvae, I.6.98ff). And the Saturnalia did continue to be celebrated as Brumalia (from bruma, winter solstice) down to the Christian era, when, by the middle of the fourth century AD, its rituals had become absorbed in the celebration of Christmas.

I'll remember when I'm celebrating that paganism predated Jesus