curious Actually only parts of the New Testament were originally in Greek. The largest part was originally written in Aramaeic, which was at the time of Jesus the language of the common people in that region.
The sources used by NT writers, yes. The gospels have some quotes in aramaic (most of which are immediately translated into Greek or whatever bible translation you are reading).
But both the gospels and the epistles were written to "make disciples of all nations" (as Mt put it), to spread the faith throughout the Roman empire. So while they had lots of Aramaic sources at their disposal (the gospels were written many decades after Jesus's works, after all, and the epistles were mostly directed at communities far from Judea), the books that eventually made it into the NT have pretty much all been written in Greek.
