The Septuagint and the Masoretic Text are the two most important textual traditions of the Hebrew Bible, and they do not always agree. The Septuagint (abbreviated LXX) is a Greek translation produced in Alexandria beginning in the 3rd century BCE. The Masoretic Text (abbreviated MT) is the Hebrew text standardized by Jewish scribes between the 7th and 10th centuries CE. They differ in language, book order, book count, and hundreds of individual readings — from minor spelling variations to entire sections that appear in one tradition but not the other.
Before the Dead Sea Scrolls were discovered in 1947, scholars often assumed the differences were simply translation errors. The scrolls told a different story.
A Greek Bible from Alexandria
The Septuagint originated in Ptolemaic Alexandria, where a large Jewish community had spoken Greek as its primary language since the city’s founding in 332 BCE. By the 3rd century BCE, these Alexandrian Jews needed their sacred texts in a language they could actually read.
The Letter of Aristeas, a 2nd-century BCE account, describes the translation’s origins: the Egyptian king Ptolemy II Philadelphus commissioned seventy-two Jewish elders to translate the Torah into Greek for the Library of Alexandria. The letter claims the translators worked independently yet produced identical translations — a detail later communities interpreted as evidence of divine guidance. Most scholars treat the Letter of Aristeas as a literary work promoting the translation’s authority rather than as straightforward historical reporting. Natalio Fernandez Marcos, in The Septuagint in Context (2000), situates the project within the broader literary culture of Ptolemaic Egypt, where translating prestigious texts into Greek was a standard practice of the royal library.
The remaining biblical books were translated over the following two centuries — different books by different hands at different times.
This piecemeal process left its mark. Karen Jobes and Moises Silva, in Invitation to the Septuagint (2000), show that translation quality varies considerably across the collection. Some books render the Hebrew quite literally; others show freer technique and interpretive choices that go well beyond word-for-word equivalence. The Septuagint is not a single translation. It is a library of translations, produced across generations.
The Septuagint also includes books absent from the Hebrew Bible entirely: Wisdom of Solomon, Sirach (Ecclesiasticus), Tobit, Judith, 1-4 Maccabees, Baruch, and additions to Daniel and Esther. These texts circulated within Greek-speaking Jewish communities and were later adopted by early Christians as part of their Old Testament.
Preserving the Hebrew Tradition
The Masoretic Text represents a different kind of textual project. The Masoretes — Jewish scribes working primarily in Tiberias and Babylonia between the 7th and 10th centuries CE — did not compose new texts. They preserved existing ones with extraordinary precision. The name itself comes from masorah, meaning “tradition.”
Their core contribution was a system of notation. The Hebrew script used for biblical texts was originally consonantal (written without vowels). Readers supplied vowels from memory and oral tradition. The Masoretes developed vowel points, accent marks, and marginal annotations (masorah parva and masorah magna) that fixed pronunciation, cantillation, and reading practice in writing for the first time.
This was an act of conservation: encoding centuries of oral reading practice into a visible system.
The oldest complete Masoretic manuscript is the Leningrad Codex, dated to 1009 CE. An earlier manuscript, the Aleppo Codex (~930 CE), was originally complete but suffered damage in 1947 and is now missing roughly 40% of its text. Both reflect the work of the Ben Asher family of Masoretes in Tiberias, whose text became authoritative for Jewish communities.
But the consonantal text the Masoretes annotated is much older than their notational work. Emanuel Tov, the Hebrew University scholar who served as editor-in-chief of the Dead Sea Scrolls publication project, has argued that the consonantal base of the Masoretic Text was largely stabilized by the 1st or 2nd century CE, following the destruction of the Second Temple in 70 CE. The Masoretes inherited a text already centuries old and added the reading apparatus around it.
Where the Two Traditions Diverge
The differences between the Septuagint and the Masoretic Text range from minor variants to structural divergences that affect how entire books read.
Book order and canon. The Masoretic Text organizes the Hebrew Bible into three sections: Torah, Prophets (Nevi’im), and Writings (Ketuvim) — the structure behind the acronym Tanakh. The Septuagint follows a different arrangement, roughly corresponding to law, history, poetry, and prophecy, and includes the additional books listed above. This canonical difference is the reason Protestant, Catholic, and Orthodox Christians have different Old Testaments today.
The book of Jeremiah offers the most dramatic example of structural divergence. The Septuagint version of Jeremiah is approximately one-eighth shorter than the Masoretic version and places the oracles against the nations in the middle of the book rather than at the end. J. Gerald Janzen, in Studies in the Text of Jeremiah (1973), argued that the shorter Septuagint text reflects an older Hebrew edition — one that was later expanded in the scribal tradition that became the Masoretic Text. This was a hypothesis. Then a Hebrew manuscript from Qumran confirmed it.
Individual readings. Hundreds of verses differ in wording. Some variations are minor (spelling, word order). Others carry real weight. In Deuteronomy 32:8, the Masoretic Text reads “according to the number of the sons of Israel,” while the Septuagint reads “according to the number of the sons of God.” One implies God divided nations by Israel’s tribal count; the other implies a divine council with multiple divine beings assigned to different nations. A Dead Sea Scroll fragment (4QDeut-j) sides with the Septuagint reading.
Chronological data. The genealogies in Genesis 5 and 11 contain different numbers in each tradition, yielding different calculations of time between creation and the flood, and between the flood and Abraham. The Septuagint’s numbers produce a longer chronology. Scholars continue to debate which set of numbers is more original.
The Dead Sea Scrolls Changed Everything
The discovery of the Dead Sea Scrolls beginning in 1947 did not merely add new data to the Septuagint-vs-Masoretic question. It overturned a fundamental assumption.
Before the scrolls, many scholars assumed the Septuagint’s differences from the Masoretic Text were the translators’ doing — mistakes, paraphrases, theological adjustments made during the Greek rendering. The scrolls revealed that some of those differences existed in the Hebrew manuscripts the translators were working from. The Greek translators had not invented those readings. They had translated them faithfully from Hebrew texts that simply differed from the Hebrew texts that later became the Masoretic tradition.
The case of Jeremiah is the clearest proof. A Hebrew manuscript from Qumran, catalogued as 4QJer-b, preserves a short version of Jeremiah that closely matches the Septuagint’s shorter text. Janzen’s 1973 hypothesis — that the Septuagint translators had been working from a genuinely different Hebrew edition — was confirmed by physical evidence.
Frank Moore Cross, the Harvard scholar who spent decades studying the Qumran biblical manuscripts, proposed a theory of “local texts” to explain this diversity. Cross argued that different textual traditions had developed in different geographical centers — Palestine, Egypt, and Babylon — before eventually being standardized. The Septuagint reflected the Egyptian text family; the Masoretic Text reflected the Babylonian; the Samaritan Pentateuch reflected the Palestinian. This model, while debated in its specifics, established that textual plurality was not an aberration to be explained away but a historical reality.
Tov, working from a broader data set as editor-in-chief of the scrolls publication, classified the Qumran biblical manuscripts into several categories: some align with the proto-Masoretic tradition, some with the Septuagint’s Hebrew parent text (Vorlage), some with the Samaritan Pentateuch, and some are independent — matching no known later tradition at all. Eugene Ulrich, another leading scrolls scholar at the University of Notre Dame, described this situation as “pluriformity”: the biblical text in the Second Temple period existed in multiple literary editions simultaneously, with the process and timing of revision different for each book.
There was no single, authoritative text of the Hebrew Bible before roughly the 2nd century CE.
Why Different Christians Use Different Bibles
The Septuagint-Masoretic divergence did not remain an ancient textual problem. It shaped the Bibles that communities read today.
Early Christians — most of whom spoke Greek — adopted the Septuagint as their Old Testament. New Testament authors quote from it frequently, sometimes in forms that differ from the Masoretic Hebrew. When the Gospel of Matthew quotes Isaiah 7:14 using the Greek word parthenos (“virgin”), it follows the Septuagint’s rendering. The Masoretic Hebrew uses almah, which means “young woman” — a difference that has generated centuries of discussion among scholars and theologians alike.
As Christianity divided into Western (Latin) and Eastern (Greek) branches, their Old Testament canons diverged along Septuagint-Masoretic lines. Jerome, composing the Latin Vulgate in the late 4th and early 5th century CE, translated primarily from the Hebrew but included the additional books. The Catholic Church designates these Septuagint-only books as “deuterocanonical” (a second layer of canon). The Orthodox churches, working from the Greek Septuagint tradition, include an even broader set.
Protestant reformers, following Jerome’s expressed preference for the Hebrew canon, excluded the deuterocanonical books — which is why Protestant Bibles have 66 books, Catholic Bibles have 73, and Orthodox Bibles have 76 or more.
These are not minor cataloguing differences. The canonical boundaries of a community’s Bible reflect centuries of decisions about which textual tradition carries authority.
What This Means for Reading the Bible Today
Every modern Bible translation sits downstream of the Septuagint-Masoretic relationship, whether its readers know it or not.
Most Protestant Old Testaments translate from the Masoretic Text. But translators regularly consult the Septuagint and the Dead Sea Scrolls when the Hebrew is unclear, damaged, or appears to have suffered corruption during transmission. The footnotes of the NRSV, for instance, frequently note “Gk” (Greek, meaning the Septuagint) or “DSS” (Dead Sea Scrolls) as alternate readings. Every modern translation is a product of comparing multiple textual traditions, not a direct copy of any single manuscript.
For readers exploring how biblical languages shaped the text, or how the Old Testament’s authorship connects to its transmission history, the Septuagint-Masoretic relationship is a central thread. Uncanon provides scholarly context alongside every passage — including the textual layers behind what you are reading.