The KJV Bible is derived from the Textus Receptus, a Greek text of the New Testament collated by Erasmus of Rotterdam around 1516-1550 AD, and from the Masoretic Text, an authoritative Hebrew and Aramaic text of the Tanakh for Judaism preserved by a group of Jewish scribes known as the Masoretes around 7th-10th century AD.
On the Textus Receptus, first, let me point out that Erasmus, a gifted scholar and polymath, was a Catholic priest who had been analysing a number of Greek manuscripts from the Byzantine church. Erasmus sought to synchronise and unify the said Greek texts into one, and also to produce a better Latin. It is believed Erasmus’s third edition of 1522 AD was used by William Tyndale, and the Stephanus printing of the third edition in 1550 AD was used by the translators of the Geneva Bible and by the translators of the King James Version Bible. Over time, Erasmus’s Greek New Testament became known as the “received text”, in Latin, Textus Receptus.
Alternatives to the texts of the Byzantines are Codex Vaticanus, which is conserved in the Vatican Library, and Codex Sinaiticus, which was discovered at Saint Catherine’s Monastery in the Sinai Peninsula in the 19th century AD. Both of these are said to be older than the texts of the Byzantines. But both are incomplete.
The Greek New Testament that is championed by modern scholars who are anti-KJV is the Novum Testamentum Graece, commonly known as NA28, after Nestle-Aland, the scholars who edited the work. It should be noted that Novum Testamentum Graece was originally the product of Cardinal Francisco Jiménez de Cisneros of the Vatican in 1514-1520 AD. It was a competitor to the 1516 AD Greek New Testament of Erasmus. You see, Erasmus went to the Greek of the Byzantines to figure out a Greek New Testament; whereas Cisneros probably used a lot of the Latin of the Vulgate to compose a Greek New Testament. Therefore, all Bible translations that are based on NA28 are in essence akin to the Latin Vulgate and the Douay Rheims. In effect, Latin to Greek to English is no different from Latin to English.
On the KJV’s translation of the Greek of Eramus’s Textus Receptus, the English poet William Blake who penned the remarkably prophetic poem “And did those feet in ancient time”, once said, the English is “almost word for word” to the Greek and “if the Hebrew is as well translated, which I do not doubt it is, we need not doubt of its having been translated as well as written by the Holy Ghost”.
So with that, let me move on to the Hebrew.
The Masoretic Text is the basis of the Tanakh of Judaism, and has certainly been so since the days of the Jewish physician, scholar and polymath Maimonides, circa 1135-1204 AD. The Masoretes transcribed between the 7th and 10th centuries AD, primarily the ben Asher family. By the way, the Masoretes were responsible for the Niqqud system of vowels, without which the pronunciation of words of Hebrew, a language of consonants, could not be written down.
Today, the oldest and most complete Masoretic Text is the Leningrad Codex, circa 11th century AD. The Aleppo Codex, circa 10th century AD, used to be the oldest but decades ago somehow some parts were lost, probably stolen. It is said that when both codices were available, the consonants of the texts matched completely.
One thing to know about Judaic texts is that traditionally it is forbidden to simply throw out old scrolls. In the past, texts that could no longer be used because the paper, papyrus or parchment had become too old or torn had to be buried. Nowadays, such texts are archived. This reverence for holy books surely means that the Tanakh has been accurately preserved over time, despite Romans 11. That said, I should add that though the Tanakh has not been corrupted, the Talmud which is a commentary or an interpretation of the Tanakh is where Judaism has gone astray.
Alternatives to the texts of the Masoretes are the Septuagint, a Greek translation of the Hebrew circa 3rd-2nd centuries BC commissioned by the Greek King of Egypt Ptolemy II Philadelphus for inclusion in the Library of Alexandria, and the Dead Sea Scrolls, aka the Qumran scrolls, discovered in 1947-1956 AD.
The Septuagint contains books not found in the Masoretic Text. Today, the Roman Catholic Church and Byzantine Church consider most of the Septuagint as scripture. Protestants, however, prefer the original Hebrew, and so disregard the extra as “Apocrypha”. It should be noted that the books that comprise the Apocrypha were not included in the original Christian canon at Nicaea, 325 AD. Significantly, Athanasius of Alexandria did not consider the extra books to be scripture, nor for that matter did Jerome who produced the first Latin Vulgate for the church at Rome. In point of fact, the books of the Apocrypha were added to the Catholic canon at the Council of Trent, in the 16th century AD, in an attempt to make Roman Catholicism even more different from Protestantism.
With regard to the Qumran scrolls, scholars now know that the scrolls were transcribed and buried by an isolated sect of Jews, a cult. The Qumran scrolls, although older, cannot possibly be more correct than the Masoretic Text because the scrolls were only discovered in the last century. Jesus Christ said, “Heaven and earth shall pass away: but my words shall not pass away”, Luke 21:33, implying scripture would have existed in some form somewhere continually since the words were first written down. Therefore, scripture could not have been buried in a cave only to surface in the last century. Also, Jesus himself, during his ministry, quoted from texts that were available at a synagogue, Luke 4:16-21, and studied from the same, Luke 2:46-49. Remember, Jesus would have read scripture in Hebrew and Aramaic, not Greek – so it would not have been the Septuagint.
For all these reasons, the Textus Receptus and the Masoretic Text are proper sources of scripture. The definitive proof of the accuracy and authenticity of scripture will of course be the fulfilment of Bible prophecy, or the lack thereof. In due time, it will be evident which Bible version is right.