It is not surprising that Paul's letter to the Roman Church is written not in Latin but in Greek. But the Greek language had to pay a price for this enormous extension of its influence. In its career of conquest it experienced important changes. Less important, no doubt, than the influence of the Greek dialects, and far less important than might have been expected, was the influence of foreign languages. But influences of a more subtle and less tangible kind were mightily at work.
Language is a reflection of the intellectual and spiritual habits of the people who use it.
Attic prose, for example, reflects the spiritual life of a small city-state, which was unified by an intense patriotism and a glorious literary tradition. It is not surprising, then, that the language of the new cosmopolitan age was very different from the original Attic dialect upon which it was founded. The Koine, then, is the Greek world language that prevailed from about 300 B.C. to the close of ancient history at about A.D. 500. The New Testament was written within this Koine period. Within this triple group, it is true, the language of the New Testament is easily supreme.