QL 94 (2013) 247-265 doi: 10.2143/QL.94.3.3007366 © 2013, all rights reserved EARLY CHRISTIAN CHRONOLOGY AND THE ORIGINS OF THE CHRISTMAS DATE In Defense of the “Calculation Theory” 1. The Recent Onslaught against the “Calculation Theory” Christmas, the feast commemorating the birth of Jesus Christ, is celebrat- ed in both the Western and Eastern churches (excepting Armenia) on 25 December. The same date once used to be the seat of the winter solstice in the Julian calendar and, as some would have it, the day on which the birth festival of the Roman sun god Sol Invictus was celebrated after its institution in 274 CE by the Emperor Aurelian. In the eyes of many ob- servers, such coincidence dictates that Christmas is best seen as an exam- ple for the “inculturation” of pagan rituals into the developing liturgical year of the Church.1 This, in a nutshell, is the basic idea behind the most 1. The amount of literature on the origins of Christmas is vast. For useful introduc- tions, see Hermann Usener, Das Weihnachtsfest (Bonn: Bouvier, 31969 [11889]); Heinrich Kellner, Heortologie (Freiburg im Breisgau: Herder, 31911) 96-118; Bernard Botte, Les origines de la Noël et de l’Épiphanie: Étude historique (Louvain: Abbaye du Mont César, 1932); Anselm Strittmatter, “Christmas and the Epiphany: Origins and Antecedents,” Thought 17 (1942) 600-626; Hieronymus Frank, “Frühgeschichte und Ursprung des römischen Weihnachtsfestes im Lichte neuerer Forschung,” Archiv für Liturgiewissen- schaft 2 (1952) 1-24; Leonard Fendt, “Der heutige Stand der Forschung über das Geburts- fest Jesu am 25. XII und über Epiphanias,” Theologische Literaturzeitung 78 (1953) 1-10; Susan K. Roll, Toward the Origins of Christmas, Liturgia Condenda, 5 (Leuven: Peeters, 1995); Ead., “The Debate on the Origins of Christmas,” Archiv für Liturgiewissenschaft 40 (1998) 1-16; Hans Förster, Die Feier der Geburt Christi in der Alten Kirche: Beiträge zur Erforschung der Anfänge des Epiphanie- und Weihnachtsfestes (Tübingen: Mohr Siebeck, 2000); Ronald Hutton, The Stations of the Sun: A History of the Ritual Year in Britain (Oxford: Oxford University Press, 1996) 1-8; Martin Wallraff, Christus Verus Sol: Sonnenverehrung und Christentum in der Spätantike (Münster: Aschendorff, 2001) 174-195. The following abbreviations are used throughout: CCSL = Corpus Chris- tianorum. Series Latina; CSCO = Corpus Scriptorum Christianorum Orientalium; CSEL = Corpus Scriptorum Ecclesiasticorum Latinorum; GCS = Die griechischen christlichen Schriftsteller der ersten drei Jahrhunderte; GCS-NF = Die griechischen … Jahrhunderte, Neue Folge; PG = Patrologiae cursus completus. Series Graeca; PL = Patrologiae… Series Latina; SC = Sources Chrétiennes. Research for this article was made possible by 248 C. Philipp E. Nothaft influential and widely held explanation of the origins of Christmas, which, for lack of a better word, may be referred to as the “History of Religions Theory” (henceforth: HRT).2 Although HRT is nowadays used as the default explanation for the choice of 25 December as Christ’s birthday, few advocates of this theory seem to be aware of how paltry the available evidence actually is. Our earliest source to mention the Natalis Invicti in conjunction with 25 De- cember comes eight decades after Aurelian with the famous Roman cal- endar that has been preserved as part of the so-called Chronograph of 354. The same Chronograph also contains a register of Christian martyrs, ordered according to their date of burial, which is headed by the birth of Christ in Bethlehem on 25 December. Since this so-called depositio martirum is attached to a similar list of Roman bishops (depositio episcoporum), whose original version dates from 336, this year is often cited as the terminus ad quem for the institution of Christmas.3 While this constellation of facts might lend credence to the notion that the birthday of Sol Invictus on 25 December preceded the dating of Jesus’s birth to that day, it remains thoroughly unclear why the fourth-century church would have adopted such a relatively new pagan festival in spite of the frequently expressed patristic disdain for paganism and its incursions into Christian practice. It is thus not surprising if a relative minority of schol- ars continues to wonder whether a different, and possibly more convinc- ing, explanation for the liturgical dating of Christ’s birth may be forth- coming. As early as 1856, the German church historian Ferdinand Piper made the suggestion that 25 December was a mere corollary of 25 March, the Leverhulme Trust funded research project “Medieval Christian and Jewish Calendar Texts,” hosted by University College London under the supervision of Prof. Sacha Stern. 2. The word “theory” would seem to capture this view’s explanatory function some- what better than the often used “history of religions hypothesis” (likewise “calculation hypothesis”), which over-emphasizes the uncertainty that is inherent to nearly all histori- cal judgment. 3. For editions of the relevant passages, see Theodor Mommsen (ed.), Chronica mi- nora saec. IV. V. VI. VII, vol. 1 (Berlin: Weidmann, 1892) 71-72, and id. (ed.), Inscriptio- nes Latinae Antiquissimae, vol. 1 (Berlin: de Gruyter, 21893) 278. The authenticity of the chronograph’s entries for “Christmas” has been disputed. See most recently Hans Förster, “Die beiden angeblich ‘ältesten Zeugen’ des Weihnachtsfestes,” Archiv für Liturgiewis- senschaft 42 (2000) 29-40; Förster, Die Feier, 95-103; Wolfgang Wischmeyer, “Die christlichen Texte im sogenannten Filocalus-Kalender,” Textsorten und Textkritik, ed. Adolf Primmer, Kurt Smolak, and Dorothea Weber (Vienna: Österr. Akad. d. Wiss., 2002) 45-57; Claudio Gianotto, “L’origine de la fête de Noël au IVe siècle,” La Nativité et le temps de Noël: Antiquité et Moyen Âge, ed. Jean-Paul Boyer and Gilles Dorival (Aix- en-Provence: Publications de l’Université de Provence, 2003) 65-79, pp. 67-68. Argu- ments in defense of authenticity are made by Józef Naumowicz, “La Calendrier de 354 et la fête de Noël,” Palamedes 2 (2007) 173-188; Alexander Zerfass, Mysterium mirabile: Poesie, Theologie und Liturgie in den Hymnen des Ambrosius von Mailand zu den Chris- tusfesten des Kirchenjahres (Tübingen: Franke, 2008) 62-63, n. 286. On the context, see now Richard W. Burgess, “The Chronograph of 354: Its Manuscripts, Contents, and History,” Journal of Late Antiquity 5 (2012) 345-396. Early Christian Chronology and the Origins of the Christmas Date 249 the date of the vernal equinox, to which the crucifixion had been assigned early on. Assuming that his earthly existence, reckoned from the concep- tion in the womb to his death, comprised a perfect number of years, early Christians fixed the incarnation of Christ on 25 March and, counting forward nine months, arrived at 25 December as the date of his birth. This is the basic idea behind the – sit venia verbo – “Calculation Theory” (CT) for Christmas, which, although it may have never been a majority view, has played a significant role in discussions of the subject.4 The problems that plague both HRT and CT were recently highlighted by the Austrian papyrologist Hans Förster, who published a well-received monograph on the origins of Christmas and Epiphany in 2007. In his book, Förster rightly emphasizes the lack of compelling evidence for HRT, which raises the question whether the Natalis Invicti celebrations on 25 December were really so ancient, widespread, and momentous as to exert a strong influence on Christian communities, in Rome and else- where.5 At the same time, however, he is highly critical of CT, which in his opinion is plagued with logical inconsistencies and with the fact that it imputes an undue amount of speculative ingenuity to the early Church fathers.6 This dismissal of the Berechnungshypothese certainly struck a chord with some of his reviewers, one of them noting that his arguments 4. Ferdinand Piper, “Der Ursprung des Weihnachtsfestes und das Datum der Geburt Christi,” Evangelischer Kalender: Siebenter Jahrgang (Berlin: Wiegandt und Grieben, 1856) 41-56. Piper’s contribution is for some reason never cited in the literature, where the invention of CT is usually credited to Louis Duchesne, Origines du culte chrétien: Étude sur la liturgie latine avant Charlemagne (Paris: Thorin, 1889) 247-254. See further Hieronymus Engberding, “Der 25. Dezember als Tag der Feier der Geburt des Herrn,” Archiv für Liturgiewissenschaft 2 (1952) 25-43; Wilhelm Hartke, Über Jahrespunkte und Feste, insbesondere das Weihnachtsfest (Berlin: Akademie Verlag, 1956); August Strobel, “Jahrpunkt-Spekulation und frühchristliches Festjahr: Ein kritischer Bericht zur Frage des Ursprungs des Weihnachtsfestes,” Theologische Literaturzeitung 87 (1962) 183-194; James F. Coakley, “Typology and the Birthday of Christ on 6 January,” V Sym- posium Syriacum, ed. René Lavenant (Rome: Pontificium Institutum Studiorum Orienta- lium, 1990) 247-256; Paul F. Bradshaw, The Search for the Origins of Christian Worship: Sources and Methods for the Study of Early Liturgy (Oxford: Oxford University Press, 22002) 187-189; Joseph F. Kelly, The Origins of Christmas (Collegeville, MN: Liturgical Press, 2004) 58-63; Frank C. Senn, The People’s Work: A Social History of the Liturgy (Minneapolis, MN: Fortress, 2006) 71-73. 5. Hans Förster, Die Anfänge von Weihnachten und Epiphanias: Eine Anfrage an die Entstehungshypothesen (Tübingen: Mohr Siebeck, 2007). The contention that Natalis Invicti on 25 December was the feast day originally instituted by Aurelian in 274 is suc- cessfully demolished by Steven Ernst Hijmans, “Sol Invictus, the Winter Solstice, and the Origins of Christmas,” Mouseion, 3rd ser., 3 (2003) 377-398. See now also id., Sol: The Sun in the Art and Religions of Rome (PhD diss., University of Groningen, 2009) 583- 595, http://dissertations.ub.rug.nl/faculties/arts/2009/s.e.hijmans. For a summary of his arguments, see C. P. E. Nothaft, “The Origins of the Christmas Date: Some Recent Trends in Historical Research,” Church History 81 (2012) 903-911. 6. Förster, Die Anfänge, 4-7, 25-39.