The Septuagint recognized by the KJV translators

Many of the King James Only viewpoint deny that the Septuagint exists, the pre-Christian translation of the Hebrew scriptures into the Greek. I don't know how they answer the King James translators themselves on this point, who in their preface written to the reader discuss the place of the Septuagint in the history of translations of the Bible. I am just now finally reading through that preface.

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From the preface to the 1611 King James Bible, The Translators to the Reader:

THE TRANSLATION OF THE OLD TESTAMENT OUT OF THE HEBREW INTO GREEK

"While God would be known only in Jacob, and have his Name great in Israel, and in none other place, while the dew lay on Gideon's fleece only, and all the earth besides was dry; then for one and the same people, which spake all of them the language of Canaan, that is, Hebrew, one and the same original in Hebrew was sufficient. [S. August. lib 12 contra Faust c32] But, when the fulness of time drew near, that the Sun of righteousness, the Son of God should come into the world, whom God ordained to be a reconciliation through faith in his blood, not of the Jew only, but also of the Greek, yea, of all them that were scattered abroad; then lo, it pleased the Lord to stir up the spirit of a Greek Prince (Greek for descent and language) even of Ptolemy Philadelph King of Egypt, to procure the translating of the Book of God out of Hebrew into Greek. This is the translation of the Seventy Interpreters, com- monly so called, which prepared the way for our Saviour among the Gen- tiles by written preaching, as Saint John Baptist did among the Jews by vocal. For the Grecians being desirous of learning, were not wont to suffer books of worth to lie moulding in Kings' libraries, but had many of their servants, ready scribes, to copy them out, and so they were dispersed and made common. Again, the Greek tongue was well known and made familiar to most inhabitants in Asia, by reason of the conquest that there the Grecians had made, as also by the Colonies, which thither they had sent. For the same causes also it was well understood in many places of Europe, yea, and of Africa too. Therefore the word of God being set forth in Greek, becometh hereby like a candle set upon a candlestick, which giveth light to all that are in the house, or like a proclamation sounded forth in the market place, which most men presently take knowledge of; and therefore that language was fittest to contain the Scriptures, both for the first Preachers of the Gospel to appeal unto for witness, and for the learners also of those times to make search and trial by. It is certain, that that Translation was not so sound and so perfect, but it needed in many places correc- tion; and who had been so sufficient for this work as the Apostles or Apostolic men? Yet it seemed good to the holy Ghost and to them, to take that which they found, (the same being for the greatest part true and sufficient) rather than making a new, in that new world and green age of the Church, to expose themselves to many exceptions and cavil- lations, as though they made a Translations to serve their own turn, and therefore bearing a witness to themselves, their witness not to be regarded. This may be supposed to be some cause, why the Translation of the Seventy was allowed to pass for current. Notwithstanding, though it was commended generally, yet it did not fully content the learned, no not of the Jews. For not long after Christ, Aquila fell in hand with a new Translation, and after him Theodotion, and after him Symmachus; yea, there was a fifth and a sixth edition, the Authors whereof were not known. [Epiphan. de mensur. et ponderibus.] These with the Seventy made up the Hexapla and were worthily and to great purpose compiled together by Origen. Howbeit the Edition of the Seventy went away with the credit, and therefore not only was placed in the midst by Origen (for the worth and excellency thereof above the rest, as Epiphanius gathered) but also was used by the Greek fathers for the ground and foundation of their Commentaries. Yea, Epiphanius above named doeth attribute so much unto it, that he holdeth the Authors thereof not only for Interpreters, but also for Prophets in some respect [S. August. 2::de dectrin. Christian c. 15]; and Justinian the Emperor enjoining the Jews his subjects to use especially the Translation of the Seventy, rendreth this reason thereof, because they were as it were enlightened with prophetical grace. Yet for all that, as the Egyptians are said of the Prophet to be men and not God, and their horses flesh and not spirit [Isa 31:3]; so it is evident, (and Saint Jerome affirmeth as much) [S. Jerome. de optimo genere interpret.] that the Seventy were Interpreters, they were not Prophets; they did many things well, as learned men; but yet as men they stumbled and fell, one while through oversight, another while through ignorance, yea, sometimes they may be noted to add to the Original, and sometimes to take from it; which made the Apostles to leave them many times, when they left the Hebrew, and to deliver the sense thereof according to the truth of the word, as the spirit gave them utterance. This may suffice touching the Greek Translations of the Old Testament."