“These manuscripts were originally written in Koiné, or ‘common’ Greek, and not all of the amateur copyists spoke the language or were even fully literate.”
There is no such thing as “Koine” Greek. According to scholars, the Greek NT is an almost literal word-for-word translation from Hebrew original documents; ergo, the translators tried to preserve what they already considered to be holy—ie, the words of Jesus—without changing them more than they had to. IE, the Greek NT is not bad Greek, but it is more like a literary rubbing from an original.
(”Koine” was an explanation invented by some scholars to try and explain why the Greek of the NT was not “classical” Greek.)
(See, for example, Carmignac, Birth of the Synoptics; and Tresmontant, the Hebrew Christ.)
The NT thus bears within it the evidence of its sources being contemporary with Jesus and the apostles.
“Furthermore, with reference to the woman caught in adultery, Eichenwald states: “Unfortunately, John didn’t write it. Scribes made it up sometime in the Middle Ages.”
That episode fits in the NT exactly where it is supposed to. Space is lacking here, but not only does it fit into the context of the entire chapter, but it is perfectly mirrored in the other book by John, Revelation, where the Accuser is “cast out”, as are the accusers in the story in John.
I thought much of the Greek text of the NT was originally written in Aramaic (sp?) and there may be some differences between the two texts. Not being a wise a*ss, just asking for information from those who know more.