Have you ever looked at the development of the Christmas festival? It is interesting and thought-provoking. I have reproduced below the article from the Encyclopaedia Britannica on Christmas so you can get a sense of what mainline historical scholarship says on the subject. The article mentions that one needs to read about the development of Epiphany also; both the Christmas and Epiphany articles are on my website here. I also provide, on my own website, some of my own comments and my own view on whether the church should celebrate Christmas. If you wish to publish pro-or anti-Christmas comments in the comment section on this post, you are more than welcome to do so, but keep in mind that I may not respond, including making a response to either further explicate or justify my own view on the matter. Anyway, to the article:
CHRISTMAS (i. e. the Mass of Christ), in the Christian Church, the festival of the nativity of the Jesus Christ. The history of this feast coheres so closely with that of Epiphany (q. v.), that what follows must be read in connexion with the article under that heading.
The earliest body of gospel tradition, represented by Mark no less than by the primitive non—Marcan document embodied in the first and third gospels, begins, not with the birth and childhood of Jesus, but with his baptism; and this order of accretion of gospel matter is faithfully reflected in the time order of the invention of feasts. The great church adopted Christmas much later than Epiphany; and before the fifth century it was no general consensus of opinion as to when it should come on the calendar, whether on the 6th of January, or the 25th of March, or the 25th of December.
The earliest identification of the 25th of December with the birthday of Christ is in a passage, otherwise unknown and probably spurious, of Theophilus of Antioch (A. D. 171-183), preserved in the Latin by the Magdeburg centuriators (i. 3, 118), to the effect that the Gauls contended that as they celebrated the birth of the Lord on the 25th of December, whatever day of the week it might be, so they ought to celebrate the Pascha on the 25th of March when the resurrection befell.
The next mention of the 25th of December is in Hippolytus’ (c. 202) commentary on Daniel iv. 23. Jesus, he says, was born at Bethlehem on the 25th of December, a Wednesday, in the 42nd year of Augustus. This passage also is almost certainly interpolated. In any case he mentions no feast, nor was such a feast congruous with the orthodox ideas of that age. As late as 245 Origen, in his eighth homily on Leviticus, repudiates as sinful the very idea of keeping the birthday of Christ “as if he were a king Pharaoh.”| The first certain of mention of Dec. 25 is in a Latin chronographer of A. D. 354, first published entire by Mommsen. It runs thus in English: “Year 1 after Christ, in the consulate of Caesar and Paulus, the Lord Jesus Christ was born on the 25th of December, a Friday and 15th day of the new moon.” Here again no festal celebration of the day is attested.
There were, however, many speculations in the 2nd century about the date of Christ’s birth. Clement of Alexandria, towards its close, mentions several such, and condemns them as superstitions. Some chronologists, he says, alleged the birth to have occurred in the twenty-eighth year of Augustus, on the 25th of Pachon, the Egyptian month, i. e. the 20th of May. These were probably the Basilidian gnostics. Others said it on the 24th or 25th of Pharmuthi, i. e. the 19th or 20th of April. Clement himself sets it on the 17th of November, 3 B. C. The author of a Latin tract, called the De Pascha computus, written in Africa in 243, sets it by private revelation, ab ipso deo inspirati, on the 28th of March. He argues that the world was created perfect, flowers in bloom, and trees in leaf, therefore in spring; also at the equinox, and when the moon just created was full. Now the moon and sun were created on a Wednesday. The 28th of March suits all these considerations. Christ, therefore, being the Sun of Righteousness, was born on 28th of March. The same symbolical reasoning led Polycarp (before 160) to set his birth on Sunday, when the world’s creation began, but his baptism on Wednesday, for it was the analogue of the sun’s creation. On such grounds certain Latins as early as 354 may have transferred the human birthday from the 6th of January to the 25th of December, which was then a Mithraic feast and is by the chronographer above referred to, but in another part of his compilation, termed Natalis invicti solis, or birthday of the unconquered Sun. Cyprian (de orat. Dom. 35) calls Christ Sol verus, Ambrose Sol novus noster (Sermo vii. 13), and such rhetoric was widespread. The Syrians and Armenians, who clung to the 6th of January, accused the Romans of sun-worship and idolatry, contending with great probability that the feast of the 25th of December had been invented by the disciples of Cerinthus and its lections by Artemon to commemorate the natural birth of Jesus. Chrysostom also testifies the 25th of December to have been from the beginning known in the West, from Thrace even as far as Gades. Ambrose, On Virgins iii. Ch. I, writing to his sister, implies that as late as the papacy of Liberius 352-356, the Birth from the Virgin was feasted together with the Marriage of Cana and the Banquet of the 4000 (Luke ix. 13), which were never feasted on any other day but Jan. 6.
Chrysostom, in a sermon preached at Antioch on Dec. 20, 386 or 388, says that some held the feast of Dec. 25 to have been held in the West, from Thrace as far as Cadiz, from the beginning. It certainly originated in the West, but spread quickly eastwards. In 353 – 361 it was observed that the court of Constantius. Basil of Caesarea (died 379) adopted it. Honorius, emperor (395 – 423) in the West, informed his mother and brother Arcadius (395 – 408) in Byzantium of how the new feast was kept in Rome, separate from the 6th of January, with its own troparia and sticharia. They adopted it, and recommended it to Chrysostom, who had long been in favor of it. Epiphanius of Crete was won over to it, as were also the other three patriarchs, Theophilus of Alexandria, John of Jerusalem, Flavian of Antioch. This was under Pope Anastasius, 398 – 400. John or Wahan of Nice, in a letter printed by Combefis in his Historia monothelitarum, affords the above details. The new feast was communicated by Proculus, patriarch of Constantinople (434 – 446), to Sahak, Cataholicos of Armenia, about 440. The letter was betrayed to the Persian king, who accused Sahak of Greek intrigues, and deposed him. However, the Armenians, at least those within the Byzantine pale, adopted it for about 30 years, but finally abandoned this together with the decrees of Chalcedon early in the 8th century. Many writers of the period 375 – 450, e. g. Epiphanius, Cassian, Asterius, Basil, Chrysostom and Jerome, contrast the new feast with that of the Baptism as that of the birth after the flesh, from which we infer that the latter was generally regarded as a birth according to the Spirit. Instructive as showing that the new feast traveled from West eastwards is the fact (noted by Usener) that in 387 the new feast was reckoned according to the Julian calendar by writers of the province of Asia, who in referring to other feasts use the reckoning of their local calendars. As early as 400 in Rome an imperial rescript includes Christmas among the three feasts (the others are Easter and Epiphany) on which theaters must be closed. Epiphany and Christmas were not made judicial non dies until 534.
For some years in the West (as late as 353 in Rome) the birth feast was appended to the baptismal feast on the 6th of January, and in Jerusalem it altogether supplanted it from about 360 to 440, when Bishop Juvenal introduced the feast of the 25th of December. The new feast was about the same time (440) finally established in Alexandria. The quadragesima of Epiphany (i. e. the feast of the presentation in the Temple, or hupaponte) continues to be celebrated in Jerusalem on the 14th of February, forty days after the 6th of January, until the reign of Justinian. In most other places it had long before been put back to the 2nd of February to suit the new Christmas. Armenian historians describe the riots, and display of armed force, without which Justinian was not able in Jerusalem to transfer this feast from the 14th to the 2nd of February.
The grounds on which the Church introduced so late as 350 – 448 a Christmas feast till then unknown, or, if known, precariously linked with the baptism, seem in the main to have been the following. (I) The transition from adult to infant baptism was proceeding rapidly in the East, and in the West was well-nigh completed. Its natural complement was a festal recognition of the fact that the divine element was present in Christ from the first, and was no new stage of spiritual promotion coeval only with the descent of the Spirit upon him at baptism. The general adoption of child baptism helps to extinguish the old view that the divine life in Jesus dated from his baptism, a view which led the Epiphany feast to be regarded as that of Jesus’ spiritual rebirth. This aspect of the feast was therefore forgotten, and its importance in every way diminished by the new and rival feast of Christmas. (2) The 4th century witnessed a rapid diffusion of Marcionite, or, as it was now called, Manichaean propaganda, the chief tenet of which was that Jesus either was was not born at all, was a mere phantasm, or anyhow did not take the flesh of the Virgin Mary. Against this view the new Christmas was a protest, since it was peculiarly the feast of his birth in the flesh, or as a man, and is constantly spoken of as such by the fathers who witnessed its institution.
In Britain the 25th of December was a festival long before the conversion to Christianity, for Bede (De temp. rat. ch. 13) relates that “the ancient peoples of the Angli began the year on the 25th of December when we now celebrate the birthday of the Lord; and the very night which is now so holy to us, they called in their tongue modranecht (modra niht), that is, the mothers’ night, by reason we suspect of the ceremonies which in that night-long vigil they performed.” With his usual reticence about matters pagan or not orthodox, Bede abstains from recording who the mothers were and what the ceremonies. In 1644 the English puritans forbad any merriment or religious services by act of Parliament, on the ground that it was a heathen festival, and ordered it to be kept as a fast. Charles II. revived the feast, but the Scots adhered to the Puritan view.
Outside Teutonic countries Christmas presents are unknown. Their places taken in Latin countries by the strenae, French etrennes, given on the 1st of January; this was in antiquity a great holiday, wherefore until late in the 4th century the Christians kept it as a day of fasting and gloom. The setting up in the Latin churches of a Christmas crèche is said to have been originated by St Francis.
AUTHORITIES.—K. A. H. Kellner, Heortologie (Freiburg im Br., 1906), with Bibliography; Hospinanius, De festis Christianorum (Genevac, 1574); Edw. Martene, De Antiquis Ecclesia Ritibus, iii. 31 (Bassani, 1788); J. C. W. Augusti, Chrisl. Archaologie, vols. i. and v. (Leipzig, 1817-1831); A. J. Binterim, Denkwurdigkeiten, v. pt. i. p. 528 (Mainz, 1825 &c.); Ernst Friedrick Wernsdorf, De originibus Solemnium Natalis Christi (Wittenberg, 1757, and in J. E. Volbeding, Thesaurus Commentationum, Lipsiae, 1847); Anton. Bynaeus, De Natali Jesu Christi (Amsterdam, 1689); Hermann Usener, Religionsgeschichtliche Untersuchungen (Bonn, 1889); Nik. Nilles, S. J., Kalendarium Manuale (Innsbruck, 1896); L. Duchesne, Origines de culte chretien (3e ed., Paris, 1889). (F. C. C.) (pgs. 293-294, The Encyclopaedia Britannica, 11th ed., vol. VI. New York: Encyclopaedia Britannica, Inc., 1911).
 In the Abhandlungen der sächsischen Akademie der Wissenschaften (1850). Note that in A. D. 1, Dec. 25 was a Sunday and not a Friday.
 In a fragment preserved by an Armenian writer, Ananias of Shirak.