Because his letters rarely mention any datable fact, could fit many different periods of history, and have had what would have been their original dates stripped out of them probably when they were edited together by cutting and pasting numerous segments of various letters into the seven real ones we know; see On the Historicity of Jesus , pp.
So how are we so sure when they were written? The preponderance of evidence weighs only for that decade. So we are asking only about those letters.
The first prong of reasoning is that the authentic Epistles were written in blatant ignorance of the coming catastrophic Jewish War of A. The second prong of reasoning is that the letters date themselves to roughly twenty years after the crucifixion and resurrection of Jesus and whether these correspond to merely believed or actual events is not relevant to the point, e. Galatians ; cf.
And all external sources that date Paul place his mission in the 30ss A. Had Paul written, say, a hundred years earlier, then that would not be a problem Mark had to solve; that ship would have sailed and thus been addressed already two lifetimes before Mark even wrote. Likewise anything else.
For example, from the Babylonian Talmud, written in the Middle Ages, we learn that at that time in history at least, there were Christians outside the Roman Empire who were placing the death of Jesus in the 70s B.
