The Original Language of the New Testament was...
There has been much debate about this in recent years. Many say Koine Greek while others have proposed a Semitic language, like Syriac or Hebrew. Therefore, we shall investigate all three. The best way to resolve this discrepancy is to simply examine the historical and archaeological evidence. First, we shall consider what evidence supports the New Testament being written in Hebrew.
Notably, the oldest existing Hebrew manuscript of the complete New Testament (henceforth "NT"), was translated by Isaac Edward Salkinson. This undertaking was funded by the British Bible Society in 1877, completed in 1883, and published in 1886.
Additionally, there are a handful of Hebrew manuscripts that predate Salkinson, but they only consist of Matthew's Gospel. The most notable are Shem Tov's from 1385, followed by Sebastian Munster's 1537, and Jean du Tillet's 1555 versions -which many consider mere adaptations from the Greek and Latin which preceded them. Meanwhile, other scholars have provided linguistic evidence of Shem Tov's Matthew coming from an earlier Hebrew text.
Gospel of Matthew Written Originally In Hebrew
In any event, there is plenty of historical evidence that the Gospel of Mattiyahu (Matthew) was originally written in Hebrew. For example, Papias, who was a companion of Polycarp, wrote in 100 AD that the Gospel of Matthew was written in Hebrew. There is also an account regarding Pantaenus, who evidently went to India and found the church which the Apostle Bartholomew had established. In their possession, was a copy of the Hebrew Gospel of Matthew that Pantaenus then brought back to Alexandria. In fact, every church historian and writer up to the time of Jerome, who died in 420 AD, said that the Gospel of Matthew was originally written in Hebrew.
Of prominent mention, is the testimony of Irenaeus -the disciple of Polycarp. In approximately 175 AD, Irenaeus wrote, "Matthew also issued a written Gospel among the Hebrews in their own dialect..." (Against Heresies 3.1:1).
Moreover, there have been continuous quotes of Matthew's Hebrew Gospel by Rabbis since shortly before 700 AD -as quoted in "The Book of Nestor the Priest". The Rabbis have used it extensively to show that keeping the Law was in line with the teachings of Yeshua HaMashiach (Jesus Christ); especially during various trials that were conducted by the False Church at Rome. The most famous were those involving the previously mentioned Shem Tov -who successfully used the Hebrew Gospel of Matthew to keep the Jews of Aragon (modern Spain) from being killed for doing what was commanded in the Law.
Now that it has been firmly established that Matthew originally penned his Gospel in Hebrew, the question remains about what language the other 26 books of the NT were originally written in. In order to answer this question, of necessity, we must look to another language -because absolutely NO other historical or archeological evidence exists supporting Hebrew as the original language of the remaining books. Therefore, we shall now examine what evidence supports the New Testament being written in Aramaic.
Aramaic Not Original Language of New Testament
The first thing to know about Aramaic is that it is not the same as Hebrew. Instead, it is a related language in the same linguistic family (Central Semitic). Aramaic; therefore, is one of five languages in the same family with only modern Hebrew, Arabic, and the Assyrian dialect of Aramaic still in use. Moreover, there has never been any manuscripts found containing any part of the NT in Jewish Aramaic. Instead, all of the Aramaic manuscripts that have been discovered are written in Syriac, ergo, the language of the Peshitta.
During the first century, it was the Osroene kingdom that proliferated this language. Osroene was a buffer kingdom between the Roman and the Parthian Empire (on the Syrian/Turkish border) where the Syriac dialect of Aramaic was the official language. It belonged to neither empire but did have nominal Parthian or Roman oversight. Until the time of Trajan in 114 AD, the Romans left it alone so it could continue as a buffer state. Hence, the universal persecution of Domitian in 95 AD did not extend to Osroene, thereby enabling the Syriac Peshitta to be translated and compiled at its capital of Edessa. So, after the king of Osroene converted to Christianity in 70 AD, he commissioned the translation of the Old Testament into Syriac, and with certainty, completed it by 100 AD.
Whereas, the earliest definite historical proof that parts of the NT had been translated into Syriac was furnished by Hegesippus in 170 AD. In fact, it appears from archaeological evidence that the translation of most of the NT into Syriac (excluding 2 Peter, 2 John, 3 John, Jude and Revelation) could have been completed by 190 AD. The remaining five books were not added until after 500 AD and subsequently became very popular in the East.
What is known for certain is that there is absolutely no evidence that the any type of Aramaic was the original language of the NT as those who first mentioned the Syriac versions all testified that they were translations from Koine Greek (or Hebrew in the case of Matthew). Accordingly, the Syriac translation of Matthew was used to help translate this gospel into Koine Greek (where Matthew's preexistent Greek version had not yet spread). This accounts for instances of transliterated Aramaic words appearing in several of the ancient Koine Greek texts of Matthew's Gospel.
Therefore, no part of the NT was originally written in any form of Aramaic based on the historical and archaeological evidence.
Evidence New Testment Written Originally In Koine Greek
Lastly, we shall now examine what evidence supports the New Testament being written in Greek. Oddly, we'll begin by reintroducing Irenaeus -the disciple of Polycarp, who wrote, "Matthew ALSO issued a written Gospel among the Hebrews in their own dialect..." (Against Heresies 3.1:1). You will notice, that implicit within Irenaeus' statement is that Matthew authored his Gospel in more than one language. This is illustrated by Irenaeus' frequent references to the widespread use of the Greek gospel, including citations of Matthew's frequent use of the Greek Septuagint as inspiration when writing his Greek Gospel (3.21:2-4).
He additionally states that Matthew made conscious choices as he wrote by the power of the Holy Spirit and then proceeds to quote statements from the Greek text of Matthew -not the Hebrew! For one example of many, notice the phrase, "And they shall call His name Immanuel, which is translated, 'God with us'" (Matthew 1:23). Now for those who spoke and read Hebrew -furnishing a definition of this name would make no sense as they already would have understood the meaning. In other words, this was a Greek text utilizing a Hebrew word requiring translation for its readers. Another mention of a Koine Greek Gospel of Matthew was made by Tertullian circa 200 AD.
In fact, every single historian from 100 AD onwards records that all of the books of the NT, were written in Koine Greek (with Matthew also existing in Hebrew). There is not one single reference by any historian within a thousand years of the writing of the NT indicating that any book was translated into Koine Greek from another language.
Notice several more examples -which by no means represents an exhaustive list:
Clement of Rome quotes passages from ten different NT books in his epistle to the Corinthian church in 95 AD. This was approximately the same year as the book of Revelation was composed by the Apostle John -definitively proving these books were already in common circulation. Several of the epistles from which Clement's word-for-word Greek quotations came -had been around for less than thirty years.
Ignatius of Antioch quotes from an incredible seventeen books of the NT in the epistles he wrote before his death in 108 AD. This includes quotes from the book of Revelation only a decade after it was written. Again, these quotations are word-for-word and are written in Koine Greek.
Polycarp in his short epistle to the Philippians written in 120 AD, also quotes word-for-word from 16 books of the NT and paraphrases passages in the remaining 11 books, also in Koine Greek. This is a fourth witness having a direct connection to both the Apostles writings, and their direct tutelage -Polycarp himself being a disciple of John.
Let us now consider a fifth witness! Polycrates, when disputing the proper date of the Passover with Victor of Rome, first establishes a succession of teaching directly from the Apostles Philip and John before recording a direct quotation from the Greek text of Acts 5:29 meaning, "we ought to obey God rather than man."
Proof Entire New Testament Existed In Koine Greek By 120 AD
Therefore, by no later than 120 AD, there is definite proof that all 27 books of the NT existed in Koine Greek. The historical evidence in support of the Greek language, compliments the archaeological evidence that we shall now briefly examine.
Among the earliest, is a fragment of the Gospel of John discovered in Egypt. It is called the Rylands Papyrus P52. This fragment contains part of chapter 18 written in 125 AD. It is one of many fragments that are dated no later than 200 AD which are all preserved in the Rylands Library. All are written in Koine Greek.
Another popular collection of NT manuscripts that have been dated no later than 200 AD is the Chester Beatty Papyri P46. This is a collection of 104 pages from an early codex (bound book) that contains almost all of the writings of the Apostle Paul. Most of the papyri in this set are complete pages with only a few lines missing at the bottom from deterioration. The Chester Beatty Papyri P45 is similar in composition and contains portions of all four Gospels and the book of Acts. It is dated at about 250 AD. The Chester Beatty Papyri P47 contains part of the book of Revelation and is also dated near 250 AD. All of these manuscripts were written in Koine Greek.
In fact, there are an incredible 10 more collections of papyri containing various portions of the NT that are dated no later than 200 AD, with many more that are dated no later than 250 AD. These collections collectively contain the entire NT and all of them are written in Koine Greek. In total, there are nearly 5800 Greek manuscripts of the New Testament still existing from antiquity.
Therefore, the overwhelming preponderance of historical and archaeological evidence makes it clear that the Gospel of Matthew was originally penned in both Hebrew and Greek, while the remaining twenty-six books of the New Testament were originally written in Koine Greek.