Ingledsva
HEATHEN ALASKAN
No one knows that.
There is solid evidence that the books were written by those claiming to have written them, and that what they wrote of Jesus of Nazareth is true.
Rylands Library Papyrus P52 disproves the theory of some critics that the Gospels are actually forgeries from the second century, and not written by Jesus’ disciples at all.
It is universally agreed that Matthew, Mark, and Luke were written before John. This is clear evidence that they were all written in the first century.
No group of frauds could possibly have produced them in the first century, when eyewitnesses of the events they related, could have refuted any false stories.
Syriac versions of the Bible
Syria played an important or even predominant role in the beginning of Christianity. Here is where the Gospel of Matthew, the Gospel of Luke, the Didache, Ignatiana, and the Gospel of Thomas were written. Syria was the country in which the Greek language intersected with the Syriac, which was closely related to the Aramaic dialect used by Jesus and the Apostles. That is why Syriac versions are highly esteemed by textual critics. Scholars have distinguished five or six different Syriac versions of all or part of the New Testament. It is possible that some translations have been lost. The Manuscripts originate in countries like Lebanon, Egypt (Sinai), Mesopotamia, Assyria, Armenia, Georgia, India, and even from China. This is good evidence for the great historical activity of the Syriac church.
Diatessaron
The Diatessaron, (c. 160–175) is the most prominent early gospel harmony, and was created by Tatian, an early Christian Assyrian apologist and ascetic. Tatian sought to combine all the textual material he found in the four gospels—Matthew, Mark, Luke, and John—into a single coherent narrative of Jesus's life and death.
Critics claiming that the four Gospels were not written till the middle of the second century were apparently wrong.
What Subduction Zone said.
You need to read some new sources.
There are many discussions concerning this topic here on RF.
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