You've probably heard a preacher quote Isaiah 7:14 about a "virgin" giving birth. What you may not know is that the New Testament writers were quoting a Greek translation of the Hebrew Bible — not the Hebrew text itself. That translation is called the Septuagint, and it's one of the most influential documents in the history of Christianity. It shaped the language of the New Testament, defined the biblical canon for millions of Christians, and is still in official use in the Greek Orthodox Church today.
If you've ever wondered why Catholic Bibles have more books than Protestant ones, or why some Old Testament quotes in the New Testament don't quite match your Bible — the Septuagint is almost always the answer.
Key Takeaways
- The Septuagint (abbreviated LXX) is the ancient Greek translation of the Hebrew Old Testament, produced roughly 250–150 BC in Alexandria, Egypt.
- The name comes from the Latin septuaginta, meaning "seventy," referring to the tradition of 72 Jewish scholars who produced it.
- The New Testament quotes the Old Testament around 300 times — the majority of those quotes follow the Septuagint, not the Hebrew.
- The Septuagint includes additional books (called deuterocanonical books) not found in the Protestant Old Testament — this explains the Catholic 73-book Bible vs. the Protestant 66-book Bible.
- The Greek Orthodox Church still uses the Septuagint as its official Old Testament text today.
- Understanding the Septuagint unlocks deeper meaning in New Testament passages and helps explain translation differences in your Bible.
What Is the Septuagint?
The Septuagint is the oldest surviving Greek translation of the Hebrew Scriptures. It's the text that most of the ancient Christian world read as their "Old Testament" before the New Testament was written, and it became the Bible that the apostles quoted from. The name comes from the Latin word septuaginta, which simply means "seventy." In scholarly shorthand, it's referred to as LXX — the Roman numeral for 70.
The Septuagint is not a single document. It's a collection of translations made by different hands over roughly a century, from about 250 BC to 150 BC. The Torah (the first five books: Genesis, Exodus, Leviticus, Numbers, Deuteronomy) was translated first, in Alexandria, Egypt. The rest of the Hebrew Scriptures followed over the following century.
The "seventy" tradition comes from a fascinating ancient document called the Letter of Aristeas. According to this letter, the Egyptian king Ptolemy II Philadelphus (who ruled from 285–246 BC) commissioned a translation of the Jewish Law for the famous Library of Alexandria. He reportedly requested 72 Jewish scholars — six from each of Israel's twelve tribes — to travel to Alexandria and complete the translation. The story says they all produced identical translations independently, a detail scholars treat as legend rather than history. But the core historical kernel — that the Torah was translated into Greek in Alexandria around 250 BC — is widely accepted by scholars, including those at Oxford Biblical Studies and Britannica.
The name "Septuagint" (and the number 70) is a rounded version of the 72 scholars in the Aristeas story. Over time, the label expanded to cover the entire Greek Old Testament, not just the Torah.
Why Was the Septuagint Created?
To understand why a Greek translation was needed, you need to understand what was happening to the Jewish world in the third century BC.
After Alexander the Great conquered the Near East (334–323 BC), Greek became the lingua franca — the common language — of the entire Mediterranean world. This period is called the Hellenistic era. Jewish communities spread throughout this Greek-speaking world — in Egypt, Syria, Asia Minor, and beyond. This is called the Jewish diaspora (Greek for "scattering").
By 250 BC, many diaspora Jews — especially those in Alexandria, Egypt — no longer spoke Hebrew or Aramaic fluently. Greek was their everyday language. They needed their Scriptures in a language they could actually read. The Septuagint was the answer.
Alexandria was the intellectual capital of the ancient world at this time. Its famous Library of Alexandria aimed to collect all human knowledge. Ptolemy II Philadelphus was an enthusiastic patron of learning who reportedly wanted a copy of the Jewish Law in his great library. The needs of the diaspora community and the ambitions of a bibliophile king converged — and the result was the Septuagint.
This Greek translation became so important that for centuries it was simply called "the Scripture" in Greek-speaking Jewish and early Christian communities. The New Testament writers grew up reading it. When they quote "the Bible," they're almost always quoting the Septuagint.
What Does the Septuagint Include?
The Septuagint contains all 39 books found in the Protestant Old Testament — the same texts found in the Hebrew Bible (called the Masoretic Text, which we'll discuss shortly). But it also includes additional books that were written or preserved in Greek.
These additional books are called deuterocanonical books (from Greek deuteros = "second" + kanon = "rule"). The word "deuterocanonical" means "second canon" — books that belong to the canon, just recognized in a second stage. Protestant traditions call these books the Apocrypha (Greek for "hidden things") and consider them valuable but not Scripture. Catholic and Orthodox traditions consider them fully canonical.
The deuterocanonical books in the Septuagint include:
- Tobit — a story of faith and family set in the Assyrian exile
- Judith — a tale of a Jewish widow who defeats a foreign general
- 1 and 2 Maccabees — historical accounts of the Maccabean revolt (167–160 BC)
- Sirach (also called Ecclesiasticus) — a book of practical wisdom similar to Proverbs
- Wisdom of Solomon — a philosophical meditation on divine wisdom
- Baruch — a short prophetic book attributed to Jeremiah's secretary
This is why Catholic Bibles contain 73 books and Protestant Bibles contain 66 books. The Catholic Church, following the ancient Septuagint tradition confirmed at the Council of Trent (1546), includes the deuterocanonical books. Most Protestant denominations, following the 16th-century Reformers who insisted on the Hebrew canon, do not include them as Scripture — though some Protestant Bibles print them in a separate Apocrypha section.
Did Jesus and the Apostles Use the Septuagint?
Yes — and this is perhaps the most important reason to understand the Septuagint.
The New Testament was written in Greek, the common language of the Roman world in the first century. When NT authors quote the Old Testament, they're almost always working from the Septuagint. Scholars at Oxford Biblical Studies estimate that roughly 300 of the approximately 350 Old Testament quotations in the New Testament follow the Septuagint text rather than the Hebrew.
One of the most striking examples is Isaiah 7:14. In the Hebrew text (the Masoretic Text), the word used is almah, which means "young woman." But in the Septuagint, the translators used the Greek word parthenos, which specifically means "virgin." When Matthew 1:23 quotes this verse — "Behold, the virgin shall conceive and bear a son" — he's following the Septuagint's parthenos, not the Hebrew almah. This single translation choice has shaped Christian theology for two thousand years.
Paul's letters are thoroughly grounded in Septuagint language. His famous phrase in Romans 3:10 — "None is righteous, no, not one" — is a composite of Psalm 14:1–3 and Psalm 53:1–3 from the Septuagint. The Letter to the Hebrews, which contains more Old Testament quotations than any other NT book, consistently follows the Septuagint text.
Even Jesus's own quotations, as recorded in the Gospels, often reflect the Septuagint. This isn't surprising: in the Greek-speaking synagogues of Galilee and Judea, the Septuagint was the version most people encountered.
Citation capsule: The Septuagint is the Bible the New Testament writers read. Approximately 300 of the NT's Old Testament quotations follow the Septuagint rather than the Hebrew Masoretic Text. Understanding which version an author is quoting is essential for reading the NT accurately. Source: Oxford Biblical Studies; Jobes & Silva, Invitation to the Septuagint (Baker Academic, 2015).
Septuagint vs. Masoretic Text
If the Septuagint is the older translation, what is the Masoretic Text?
The Masoretic Text (often abbreviated MT) is the authoritative Hebrew text of the Old Testament, compiled and vocalized by a group of Jewish scribes known as the Masoretes. They worked from roughly AD 600 to AD 1000, and the standard Masoretic Text was finalized around AD 900–1000. This is the Hebrew text behind most modern Protestant Old Testament translations, including the ESV, NIV, NASB, and KJV.
Here's the important point: the Masoretic Text is about 1,200 years younger than the Septuagint translation it's often compared against. The Septuagint was translated from Hebrew manuscripts that existed in 250 BC — manuscripts we no longer have.
So which is more accurate? The answer isn't simple. The discovery of the Dead Sea Scrolls (1947–1956) gave scholars ancient Hebrew manuscripts dating from about 250 BC to AD 68 — nearly 1,000 years older than the Masoretic Text. Remarkably, the Dead Sea Scrolls sometimes agree with the Septuagint against the Masoretic Text, and sometimes agree with the Masoretic Text against the Septuagint. This tells us that different Hebrew textual traditions existed in the Second Temple period, and the Septuagint translators were faithfully translating one of them.
Some specific differences include:
- Psalms numbering: The Septuagint often assigns different numbers to the Psalms. For example, Psalm 23 ("The Lord is my shepherd") in the Masoretic Text is Psalm 22 in the Septuagint. This is why Greek and Eastern Orthodox liturgical books use different Psalm numbers.
- Jeremiah: The Septuagint version of Jeremiah is about one-eighth shorter than the Masoretic Text version — and a Dead Sea Scroll fragment of Jeremiah supports the shorter version.
- Minor word differences appear throughout both texts, many of which affect the nuance of theological passages.
Neither text is simply "wrong." They represent different manuscript traditions of an ancient text — and both have contributed to the rich history of biblical interpretation.
Who Uses the Septuagint Today?
The Septuagint isn't just a historical curiosity — it's a living text for millions of Christians worldwide.
Greek Orthodox Church: The Septuagint is the official Old Testament of the Greek Orthodox Church and has been since the early centuries of Christianity. The Divine Liturgy of St. John Chrysostom reads from the Septuagint, and Orthodox theological education is grounded in it.
Other Eastern Orthodox Churches: The Russian Orthodox Church, Serbian Orthodox Church, Romanian Orthodox Church, and other autocephalous Orthodox churches use Septuagint-based Old Testament translations in their liturgies.
Catholic Church: While the Catholic Church's official Bible is the Latin Vulgate (Jerome's 4th-century translation, which used a mix of Hebrew and Greek sources), the deuterocanonical books that Catholics accept as Scripture come from the Septuagint tradition. The Septuagint is recognized as the Old Testament tradition of the early Church.
Protestant scholars: Protestant biblical scholars use the Septuagint extensively as a critical tool for understanding the New Testament and for textual criticism of the Hebrew Bible. It's a standard subject in seminary curricula worldwide.
Why Should You Care About the Septuagint?
Even if you're a casual Bible reader with no interest in ancient languages, the Septuagint affects your Bible reading in concrete ways:
1. It explains New Testament quotes that seem slightly "off." If you've ever compared a NT quote to its OT source and noticed they don't quite match, the Septuagint is usually why. The NT author is quoting the Greek text, and you're reading a translation of the Hebrew. Knowing this prevents confusion and opens up layers of meaning.
2. It explains the 73-book vs. 66-book difference. If you've ever talked with a Catholic or Orthodox Christian about the Bible and been puzzled by the extra books, the Septuagint is the historical root of that difference. It's not about adding or removing books for theological convenience — it's about which ancient textual tradition your church follows.
3. It shows how the early church understood the Old Testament. The Church Fathers — Origen, Augustine, Jerome, John Chrysostom — all worked with the Septuagint as their primary Old Testament. Reading their writings through a Septuagint lens helps you understand what they actually meant.
4. It enriches your understanding of specific passages. The Greek wording of the Septuagint often carries theological weight that Hebrew doesn't. The Septuagint's use of parthenos (virgin) in Isaiah 7:14, or kyrios (Lord) throughout the Psalms, shaped how early Christians understood those passages — and those Greek terms echo throughout the New Testament.
Citation capsule: The Septuagint is not merely a historical artifact. It is the Old Testament that shaped the New Testament authors' vocabulary, the early Church's theology, and the canon of Scripture used by hundreds of millions of Orthodox and Catholic Christians today. For any serious Bible student, understanding the Septuagint is non-negotiable. Source: Britannica, "Septuagint"; N.T. Wright, The New Testament and the People of God (Fortress Press, 1992).
Can You Read the Septuagint?
You don't need to know ancient Greek to engage with the Septuagint. Several English translations are available:
Brenton's Septuagint (1844): Sir Lancelot Charles Lee Brenton's translation is the oldest widely available English Septuagint. It's in the public domain and freely available online. It's readable but dated — the English style reflects 19th-century translation conventions.
New English Translation of the Septuagint (NETS): Published by Oxford University Press, the NETS (2007) is the modern scholarly standard for an English Septuagint. It's highly accurate, uses contemporary English, and is ideal for serious study. It's available in print and online at netsepta.org.
Orthodox Study Bible: Published by Thomas Nelson, the Orthodox Study Bible uses a Septuagint-based Old Testament (drawn from Brenton and revised) alongside the New King James Version New Testament. It includes extensive notes from Eastern Orthodox tradition.
Lexham English Septuagint (LES): A more recent (2019) translation produced by Lexham Press, available in digital form through Logos Bible Software.
For everyday Bible exploration, using one of these alongside your regular Bible can open up surprising new dimensions in Old Testament passages — especially the Psalms, Isaiah, and the wisdom literature.
If you'd like to explore how the Septuagint compares with your current Bible translation, our Bible Expert AI can walk you through specific passages and help you see the differences side by side.
Frequently Asked Questions
What does LXX stand for? LXX is the Roman numeral for 70. It's the standard abbreviation for the Septuagint, based on the ancient tradition that 70 (or 72) Jewish scholars produced the Greek translation. Scholars, clergy, and Bible students use "LXX" and "Septuagint" interchangeably.
Is the Septuagint the same as the Greek New Testament? No. The Septuagint is a Greek translation of the Old Testament, produced roughly 250–150 BC. The New Testament was originally written in Greek, between approximately AD 50 and AD 100. They're related — the NT authors quote the Septuagint extensively — but they are distinct collections of texts.
Why does the Septuagint say "virgin" when the Hebrew says "young woman" in Isaiah 7:14? The Hebrew word almah means a young woman of marriageable age, which typically implied virginity in that cultural context but didn't specify it grammatically. The Septuagint translators chose the Greek parthenos, which specifically means "virgin." Matthew 1:23 quotes this verse from the Septuagint, making the "virgin birth" prophecy explicit. This translation choice has been central to Christological interpretation since the first century.
Did the early church use the Septuagint or the Hebrew Bible? The early church — especially in Greek-speaking communities throughout the Roman Empire — primarily used the Septuagint. The New Testament itself reflects this: virtually all its Old Testament quotations follow the Septuagint. The Hebrew text wasn't widely accessible to Gentile Christians, most of whom didn't know Hebrew.
Why do Catholic Bibles have more books than Protestant Bibles? Catholic Bibles include seven deuterocanonical books (Tobit, Judith, 1–2 Maccabees, Wisdom, Sirach, Baruch) plus additions to Esther and Daniel that are found in the Septuagint but not in the Hebrew Masoretic Text. Protestant Reformers in the 16th century followed the Hebrew canon, excluding these books from their Old Testament. The Council of Trent (1546) confirmed the deuterocanonical books as fully canonical for Catholics.
Is the Septuagint still used in church today? Yes. The Greek Orthodox Church uses the Septuagint as its official Old Testament in worship and theology. Other Eastern Orthodox churches use Septuagint-based translations in their liturgies. The Catholic Church recognizes the Septuagint as the ancient Old Testament of the Church, and its deuterocanonical books remain part of the Catholic biblical canon.