Text and Manuscripts
What is the difference between the Septuagint and the Masoretic Text?
The Septuagint is the original Greek Old Testament. The Masoretic Text is the edited, redacted form of that scripture.
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The short answer
The Septuagint is the Greek Old Testament, begun with the Law in the third century BC and finished in the centuries that followed. It is the original. The Masoretic Text is the edited, redacted form. Jewish scribes called the Masoretes added its vowels, accents, and notes between the seventh and tenth centuries AD. They edited and deleted scripture, for reasons we cannot truly say. Where the two differ, the New Testament quotes the Septuagint.
What each text is
The name Septuagint means "seventy," after an old report that Jewish scholars translated the Law, most likely in Alexandria. The five books of Moses were translated in the third century BC. The remaining books followed later, chiefly in the second century BC, and some perhaps into the first. This became the Old Testament of Greek-speaking Jews and of the early church.
The Masoretes, from the seventh to the tenth century AD, added the vowels, accents, and notes, and counted words and letters. The consonants themselves are much older. The great early witnesses of the complete pointed system are the Aleppo Codex, about 930, and the Leningrad Codex of 1008 or 1009, the oldest complete Hebrew Bible still extant. English Bibles such as the King James Version follow this later tradition.
The Masoretes edited and deleted scripture, for reasons we cannot truly say. They cut lines the New Testament quotes, and they changed wording the apostles cite. God preserved the Scriptures. The Septuagint is the original.
More than one Hebrew family
The Dead Sea Scrolls, from about the third century BC to the first century AD, show more than one Hebrew form in use long before those medieval codices. 1QIsaa is close to the later Masoretic Isaiah, though not identical. 4QSama often agrees with the Septuagint of Samuel, and 4QJerb and 4QJerd support the shorter Greek Jeremiah. Many differences already existed in Hebrew. They are not best explained as Greek translators inventing a new Bible.
Where the wording differs
A few passages make the difference plain, especially where the New Testament quotes the Old. Read them in the compare view.
In the psalm Hebrews places on the lips of Christ, Brenton reads Psalm 39:7 LXX (40:6 KJV). LXX2012 numbers the same line as Psalm 39:6.
“Sacrifice and offering thou wouldest not; but a body hast thou prepared me: whole-burnt-offering and [sacrifice] for sin thou didst not require.”
“Sacrifice and offering thou didst not desire; mine ears hast thou opened: burnt offering and sin offering hast thou not required.”
Hebrews 10:5 follows the Greek: "a body hast thou prepared me". "mine ears hast thou opened" is the Masoretic edit of the reading Hebrews quotes, and the KJV translates that edit. The Septuagint reading is the one the New Testament carries.
Deuteronomy 32:43 in the Septuagint keeps the call for the heavens to rejoice and the line "let all the angels of God worship him". The Masoretes deleted that line, and the KJV follows the edited text. 4QDeutq still has the call for the heavens to rejoice. The wording about the angels was not invented for the New Testament. Hebrews 1:6 cites it of the Son.
“Rejoice, ye heavens, with him, and let all the angels of God worship him; rejoice ye Gentiles, with his people, and let all the sons of God strengthen themselves in him; for he will avenge the blood of his sons, and he will render vengeance, and recompense justice to his enemies, and will reward them that hate him; and the Lord shall purge the land of his people.”
“Rejoice, O ye nations, with his people: for he will avenge the blood of his servants, and will render vengeance to his adversaries, and will be merciful unto his land, and to his people.”
“And again, when he bringeth in the firstbegotten into the world, he saith, And let all the angels of God worship him.”
Isaiah 7:14 uses the Greek word parthenos in the Septuagint, and Matthew 1:23 follows that Greek. The later Hebrew word is often discussed as meaning a young woman, but the KJV of Isaiah 7:14 also reads "a virgin", so the English columns are close. The force of the difference is in the Greek Matthew quotes, and in details such as "in the womb" and "bring forth a son".
“Therefore the Lord himself shall give you a sign; behold, a virgin shall conceive in the womb, and shall bring forth a son, and you shall call his name Emmanuel.”
“Behold, a virgin shall be with child, and shall bring forth a son, and they shall call his name Emmanuel, which being interpreted is, God with us.”
At the council in Acts, James quotes Amos in the Greek form: "the remnant of men, and all the Gentiles upon whom my name is called". The later Hebrew, as in the KJV, has "the remnant of Edom". Acts 15:17 follows the Greek: "the residue of men might seek after the Lord, and all the Gentiles, upon whom my name is called".
“that the remnant of men, and all the Gentiles upon whom my name is called, may earnestly seek [me], says the Lord who does all these things.”
“That they may possess the remnant of Edom, and of all the heathen, which are called by my name, saith the Lord that doeth this.”
The Masoretes changed the Genesis 5 ages from the original numbers. In the Masoretic text, many patriarchs are a hundred years younger before the named son is born. Jared is the same in both. A few later figures were changed the other way. From Adam to the birth of Noah, Genesis 5 totals 1,642 years in the LXX2012 text and 1,056 years in the KJV.
“And Adam lived two hundred and thirty years, and begot [a son] after his [own] form, and after his [own] image, and he called his name Seth.”
“And Adam lived an hundred and thirty years, and begat a son in his own likeness, after his image; and called his name Seth:”
Why the comparison matters
The Septuagint is the original Old Testament, and the word the apostles quoted. The aim is to hear Christ more clearly: the virgin-born Emmanuel, the Son whom the angels worship, the One given a body to do the Father's will. That body was offered once, that all might be reconciled to Him and escape judgment.