Numerous efforts have been made to determine the biblical date of Creation, yielding varying results. Besides differences in interpretation, which version of the Bible is being referenced also impacts on the result. Two dominant dates for creation using such models exist. These were calculated from the genealogies in two versions of the Bible, with most of the difference arising from two versions of the Book of Genesis. Patriarchs from Adam to Terah, the father of Abraham, are said to be older by as much as 100 years or more when they begat their named son in the Greek Christian Septuagint than they were in the Latin Christian Vulgate (Genesis 5; Genesis 11) or the Hebrew Jewish Tanakh (Gen 5; Gen 11). The net difference between the two major genealogies of Genesis was 1466 years (ignoring the "second year after the flood" ambiguity), which is virtually all of the 1500-year difference between 5500 BC and 4000 BC. (See Dating creation.)
- The older dates about 5500 BC are based on the Greek (Christian) Septuagint. The Byzantine calendar has been in general use at one time in the Christian Orthodox Churches and several Eastern European countries.
- The younger dates about 4000 BC are based on the Hebrew Jewish Masoretic text. The Hebrew calendar era is used within the Jewish communities for religious and other purposes.
Jewish tradition 
During the Talmudic era, from the 1st to the 10th centuries AD, the center of world Judaism was in the Middle East, primarily in the Talmudic Academies of Iraq and Palestine. Jews in these regions used Seleucid Era dating (also known as the "Anno Graecorum (AG)" or the "Era of Contracts") as the primary method for calculating the calendar year. For example, the writings of Josephus and the Books of the Maccabees used Seleucid Era dating exclusively, and the Avodah Zarah states:
Rav Aha b. Jacob then put this question: How do we know that our Era [of Documents] is connected with the Kingdom of Greece at all? Why not say that it is reckoned from the Exodus from Egypt, omitting the first thousand years and giving the years of the next thousand? In that case, the document is really post-dated!
Said Rav Nahman: In the Diaspora the Greek Era alone is used. He [the questioner] thought that Rav Nahman wanted to dispose of him anyhow, but when he went and studied it thoroughly he found that it is indeed taught [in a Baraita]: In the Diaspora the Greek Era alone is used.
Occasionally in Talmudic writings, reference was made to other starting points for eras, such as Destruction Era dating, being the number of years since the 70 AD destruction of the Second Temple, and the number of years since the Creation year based on the calculation in the Seder Olam Rabbah of Rabbi Jose ben Halafta in about 160 AD. By his calculation, based on the Masoretic Text, Adam and Eve were created on 1st of Tishrei (Rosh Hashanah Day 1) in 3760 BC, later confirmed by the Muslim chronologist al-Biruni as 3448 years before the Seleucid era. An example is the c. 8th-century AD Baraita of Samuel.
In the 8th and 9th centuries AD, the center of Jewish life moved from Babylonia to Europe, so calculations from the Seleucid era "became meaningless". In 1178 AD, Maimonides wrote in the Mishneh Torah, Sanctification of the Moon (11.16), that he had chosen the Epoch from which calculations of all dates should be as "the third day of Nisan in this present year ... which is the year 4938 of the creation of the world" (March 22, 1178 AD). He included all the rules for the calculated calendar and their scriptural basis, including the modern epochal year in his work, and beginning formal usage of the anno mundi era. From the 11th century, anno mundi dating became dominant throughout most of the world's Jewish communities
Today, the rules detailed in Maimonides' calendrical code are those generally used by Jewish communities throughout the world. The first day of creation was the 25th of Elul, 3761 BC, on which God created existence, time, matter, darkness and light out of nothing. On the sixth day of creation (Rosh Hashanah Day 1), God created Adam and Eve, this was the 1st of Tishrei, 3760 BC.—new epoch .
Greek tradition 
Early Christian chronographers have also calculated Creation. Their computations were based on the Septuagint, which was the Greek version of the Christian Old Testament in general use by Christians until a translation in c. 405 into Latin, called the Vulgate (Genesis 5; Genesis 11), which translated interpretatively from the Jewish Masoretic Text, came into general use in Western Christianity.
Earliest Christian chronology 
The earliest extant Christian writings on the age of the world according to the biblical chronology are by Theophilus (AD 115-181), the sixth bishop of Antioch, in Apology to Autolycus (Apologia ad Autolycum), and by Julius Africanus (AD 200-245) in his Five Books of Chronology. Both of these early Christian writers followed the Septuagint version of the Old Testament, which was the version in use by most Christians at the time.
Theophilus presents a detailed chronology “from the foundation of the world" to emperor Marcus Aurelius. His chronology begins with the biblical first man Adam through to emperor Marcus Aurelius, in whose reign Theophilus lived. The chronology puts the creation of the world at about 5529 BC: "All the years from the creation of the world amount to a total of 5,698 years." No mention of Jesus of Nazareth is made in his chronology. Seraphim Rose corrected the date to about 5530 BC, to recognise that there is no year 0.
Dr. Ben Zion Wacholder points out that the writings of the Church Fathers on this subject are of vital significance (even though he disagrees with their chronological system based on the authenticity of the Septuagint, as compared to that of the Hebrew text), in that through the Christian chronographers a window to the earlier Hellenistic biblical chronographers[note 1] is preserved:
- An immense intellectual effort was expended during the Hellenistic period by both Jews and pagans to date creation, the flood, exodus, building of the Temple... In the course of their studies, men such as Tatian of Antioch (flourished in 180), Clement of Alexandria (died before 215), Hippolytus of Rome (died in 235), Julius Africanus of Jerusalem (died after 240), Eusebius of Caesarea in Palestine (260-340), and Pseudo-Justin frequently quoted their predecessors, the Graeco-Jewish biblical chronographers of the Hellenistic period, thereby allowing discernment of more distant scholarship.
The Chronicon of Eusebius (early 4th century) and Jerome (c. 380, Constantinople) dated Creation to 5199 BC. Earlier editions of the Roman Martyrology for Christmas Day used this date, as did the Irish Annals of the Four Masters.
Alexandrian era 
The Alexandrian era, developed in AD 412, was the precursor to the Byzantine era. After the initial attempts by Hippolytus, Clement of Alexandria and others, the Alexandrian computation of the date of creation was worked out to be 25 March 5493 BC.
The Alexandrian monk Panodoros reckoned 5904 years from Adam to the year AD 412. His years began with 29 August, corresponding to the First of Thoth, or the Egyptian new year.Annianos of Alexandria however, preferred the Annunciation style as New Year's Day, 25 March, and shifted the Panodoros era by about six months, to begin on 25 March. This created the Alexandrian era, whose first day was the first day of the proleptic[note 2] Alexandrian civil year in progress, 29 August 5493 BC, with the ecclesiastical year beginning on 25 March 5493 BC.
- This system presents in a masterly sort of way the mystical coincidence of the three main dates of the world's history: the beginning of Creation, the Incarnation, and the Resurrection of Christ. All these events happened, according to the Alexandrian chronology, on the 25th of March; furthermore, the first two events were separated by the period of exactly 5500 years; the first and the third one occurred on Sunday — the sacred day of the beginning of the Creation and its renovation through Christ.
Dionysius of Alexandria had earlier emphatically quoted mystical justifications for the choice of 25 March as the start of the year:
- March 25 was considered to be the anniversary of Creation itself. It was the first day of the year in the medieval Julian calendar and the nominal vernal equinox (it had been the actual equinox at the time when the Julian calendar was originally designed). Considering that Christ was conceived at that date turned March 25 into the Feast of the Annunciation which had to be followed, nine months later, by the celebration of the birth of Christ, Christmas, on December 25.
The Alexandrian Era of 25 March 5493 BC was adopted by church fathers such as Maximus the Confessor and Theophanes the Confessor, as well as chroniclers such as George Syncellus. Its striking mysticism made it popular in Byzantium especially in monastic circles. However this masterpiece of Christian symbolism had two serious weak points: historical inaccuracy surrounding the date of Resurrection as determined by its Easter computus,[note 3] and its contradiction to the chronology of the Gospel of St John regarding the date of the Crucifixion on Friday after the Passover.
Chronicon Paschale 
A new variant of the World Era was suggested in the Chronicon Paschale, a valuable Byzantine universal chronicle of the world, composed about the year 630 AD by some representative of the Antiochian scholarly tradition. It dates the creation of Adam to 21 March 5507 BC.
For its influence on Greek Christian chronology, and also because of its wide scope, the "Chronicon Paschale" takes its place beside Eusebius, and the chronicle of the monk Georgius Syncellus which was so important in the Middle Ages; but in respect of form it is inferior to these works.
Adoption of Byzantine era 
The Byzantine Anno Mundi era was the official calendar of the Eastern Orthodox Church from c. AD 691 to 1728 in the Ecumenical Patriarchate. By the late 10th century the Byzantine era, which had become fixed at 1 September 5509 BC since at least the mid-7th century (differing by 16 years from the Alexandrian date, and 2 years from the Chronicon Paschale), had become the widely accepted calendar by Chalcedonian Christianity. The Byzantine era was used as the civil calendar by the Byzantine Empire from AD 988 to 1453, and by Russia from c. AD 988 to 1700.
The computation was derived from the Septuagint version of the Bible, and placed the date of Creation at 5509 years before the Incarnation. Its year one, the supposed date of creation, was 1 September 5509 to 31 August 5508 BC.
The Etos Kosmou ("Year of the Universe") is the corresponding concept in the Byzantine calendar.
Roman tradition 
Western Christianity never adopted an Anno Mundi epoch system, relying instead on the Anno Domini (AD) epoch system, though AM dating continued to be important in theology since such dating was of direct relevance to the calculation of the Last Judgment; Bede, for instance, in De Temporum Ratione, recalculates the birth of Jesus at 3952 AM, "thus postponing the date of the apocalypse over 1200 years to 2048 AD."
Muslim tradition 
The Islamic world never adopted an Anno Mundi epoch system. Instead, year 1 of the Islamic calendar begins on July 16, AD 622, the start of the Hegira. Year numbers in the Islamic calendar are marked "AH", for anno Hegirae, meaning "in the year of the Hegira".
See also 
- Anno Lucis
- Byzantine calendar
- Chronology of the Bible
- Dating Creation
- Epoch (reference date)
- Hebrew calendar
- Young Earth creationism
- Eratosthenes of Cyrene (275-194 BC) represented contemporary Alexandrian scholarship; Eupolemus, a Palestinian Jew and a friend of Judah Maccabee, writing in 158 BC, is said to have been the first historian who synchronized Greek history in accordance with the theory of the Mosaic origin of culture. By the time of the 1st century BC, a world chronicle had synchronized Jewish and Greek history and had gained international circulation: Alexander Polyhistor (flourishing in 85-35 BC); Varro (116-27 BC); Ptolemy priest of Mendes (50 BC), who is cited by Tatian (Oratio ad Graecos, 38); Apion (1st century AD); Thrasyllus (before AD 36); and Thallus (1st century AD) - all cited chronicles which had incorporated the dates of the Noachite flood and the exodus. (Dr. Ben Zion Wacholder. "Biblical Chronology in the Hellenistic World Chronicles". in The Harvard Theological Review, Vol.61, No.3 (July 1968), pp.451–452.)
- A calendar obtained by extension earlier in time than its invention or implementation is called the "proleptic" version of the calendar.
- In the commonly used 19‐year Easter moon cycle, there was no year when the Passover (the first spring full moon, Nisan 14) would coincide with Friday and the traditional date of the Passion, 25 March; according to Alexandrian system the date would have to have been Anno Mundi 5533 = 42(!)AD.
- Benjaminson, Chani. "How old was Moses when The Torah was given at Mount Sinai". Chabad-Lubavitch Media Center. Retrieved 15 February 2013.
- "Septuagint GENESIS - 5". The Greek Old Testament (Septuagint). Elpenor. Retrieved 15 February 2013.
- "Septuagint GENESIS - 11". The Greek Old Testament (Septuagint). Elpenor. Retrieved 15 February 2013.
- Septuagint, Genesis
- Gen 5
- Chronology of the Old Testament, Dr. Floyd Nolen Jones "When the center of Jewish life moved from Babylonia to Europe during the 8th and 9th centuries AD, calculations from the Seleucid era became meaningless. Over those centuries, it was replaced by that of the anno mundi era of the Seder Olam. From the 11th century, anno mundi dating became dominant throughout most of the world's Jewish communities."
- Avodah Zarah, tractate 10
- Avodah Zarah, tractate 9 Footnote: "The Eras in use among Jews in Talmudic Times are: (a) ERA OF CONTRACTS [H] dating from the year 380 before the Destruction of the Second Temple (312-1 BCE) when, at the Battle of Gaza, Seleucus Nicator, one of the followers of Alexander the Great, gained dominion over Palestine. It is also termed Seleucid or Greek Era [H]. Its designation as Alexandrian Era connecting it with Alexander the Great (Maim. Yad, Gerushin 1, 27) is an anachronism, since Alexander died in 323 BCE — eleven years before this Era began (v. E. Mahler, Handbuch der judischen Chronologie, p. 145). This Era, which is first mentioned in Mac. I, 10, and was used by notaries or scribes for dating all civil contracts, was generally in vogue in eastern countries till the 16th cent, and was employed even in the 19th cent, among the Jews of Yemen, in South Arabia (Eben Saphir, Lyck, 1866, p. 62b). (b) THE ERA OF THE DESTRUCTION (of the Second Temple) [H] the year 1 of which corresponds to 381 of the Seleucid Era, and 69-70 of the Christian Era. This Era was mainly employed by the Rabbis and was in use in Palestine for several centuries, and even in the later Middle Ages documents were dated by it. One of the recently discovered Genizah documents bears the date 13 Tammuz 987 after the Destruction of the Temple — i.e. 917 C.E. — (Op. cit. p. 152, also Marmorstein ZDMG, Vol. VI, p. 640). The difference between the two Eras as far as the tens and units are concerned is thus 20. If therefore a Tanna, say in the year 156 Era of Dest. (225 C.E.), while remembering, naturally, the century, is uncertain about the tens and units, he should ask the notary what year it is according to his — Seleucid — era. He will get the answer 536 (156 + 380), on adding 20 to which he would get 556, the last two figures giving him the year  56 of the Era of Destruction."
- p.107, Kantor
- "Birthday of Adam & Eve (3760 BCE)". Jewish History. Chabad-Lubavitch Media Center. Retrieved 15 February 2013.
- "Creation (3761 BCE)". Jewish History. Chabad-Lubavitch Media Center. Retrieved 15 February 2013.
- "To find the corresponding Jewish year for any year on the Gregorian calendar, add 3760 to the Gregorian number, if it is before Rosh Hashanah. After Rosh Hashanah, add 3761. " "The Jewish year". About the Jewish Calendar. Chabad-Lubavitch Media Center. Retrieved 15 February 2013.
- See The Remaining Signs of Past Centuries.
- The Easter Computus and the Origins of the Christian Era, Alden A. Mosshammer
- Tauber, adapted by Yanki. "The Man in man". High Holidays Rosh Hashanah Study Essays. Chabad-Lubavitch Media Center. Retrieved 15 February 2013.
- Theophilus of Antioch. Theophilus of Antioch to Autolycus. Book III. Chap XXIV (Chronology from Adam) - Chap. XXVIII (Leading Chronological Epochs).
- Julius Africanus. Extant Writings III. The Extant Fragments of the Five Books of the Chronography of Julius Africanus.
- Theophilus, Apologia ad Autolycum, Book III Chapters 24-27
- Theophilus, Apologia ad Autolycum, Book III Chapters 28
- Fr. Seraphim Rose. Genesis, Creation and Early Man: The Orthodox Christian Vision. St. Herman of Alaska Brotherhood, Platina, California, 2000. ISBN 978-1-887904-02-5. p.236.
- Dr. Ben Zion Wacholder. "Biblical Chronology in the Hellenistic World Chronicles". in The Harvard Theological Review, Vol.61, No.3 (Jul., 1968), pp.451–452.
- The Penn Commentary on Piers Plowman by Andrew Galloway page 69
- Fourth Century (see 327 Eusebius of Caesarea). Archived 2009-10-25.
- Howlett, J.A. (1913). "Biblical Chronology". Catholic Encyclopedia. New York: Robert Appleton Company.
- from 5194 AM in the Annals at CELT — University College Cork's Corpus of Electronic Texts project has the full text of the annals online, both in the original Irish and in O'Donovan's translation
- Elias J Bickerman (1980). Chronology of the Ancient World (Aspects of Greek & Roman Life) (2nd sub ed.). Ithaca, N.Y.: Cornell Univ. Press. p. 73. ISBN 0-8014-1282-X.
- Rev. Philip Schaff (1819–1893), Ed. "Era." Schaff-Herzog Encyclopedia of Religious Knowledge. New Edition, 13 Vols., 1908-14. Vol. 4, pp.163.
- Pavel Kuzenkov (Moscow). "How old is the World? The Byzantine era κατα Ρωμαίους and its rivals". 21st International Congress of Byzantine Studies, London 2006. pp.2–4.
- George Synkellos. The Chronography of George Synkellos: a Byzantine Chronicle of Universal History from the Creation. Transl. Prof. Dr. William Adler & Paul Tuffin. Oxford: Oxford University Press, 2002.
- Van der Essen, L. "Chronicon Paschale". In The Catholic Encyclopedia (New Advent). New York: Robert Appleton Company, 1908.
- Landes, Richard (1995). Relics, Apocalypse, and the Deceits of History. Cambridge: Harvard UP. p. 291.
- Duncan, Edwin (1999). "Fears of the Apocalypse: The Anglo-Saxons and the Coming of the First Millennium". Religion & Literature 31 (1): 15–23; 23 n.6.
- Trawicky, Bernard (2000). Anniversaries and Holidays. American Library Association. p. 232. ISBN 0838906958.
- S.O.M.A. (2010). Soma's Dictionary of Latin Quotations, Maxims and Phrases. Trafford Publishing. p. 71. ISBN 1425144977.
- Mattis, Kantor, The Jewish time line encyclopedia: a year-by-year history from Creation to present, Jason Aronson Inc., Northvale, N.J., 1992