Luke Timothy Johnson on Greek and Responsible Reading of the New Testament
"The New Testament is written in first-century Greek: diction, grammar, and syntax are not subject to the whim of readers. Writings can say only what the Koine of that time allows them to say. The only truly responsible reading of the New Testament, consequently, is one based on the Greek text in its historical specificity." - Luke Timothy Johnson, The New Testament: A Very Short Introduction (Oxford: 2010), 5.
One could say the same thing, of course, about the Old Testament and Hebrew.