Historian and author Tom Holland, while not a Christian, came to realize as he studied the classical world that the Western values and morals he cherished came not from Greece and Rome, but from Christianity (see here).
On an Unbelievable? podcast, Holland had a discussion with N.T. Wright on the question “How Did St. Paul Change the World?” In the clip below, you can hear him talk about how he came to recognize the dramatic influence Christianity had on the world. (You can watch the full hour-long discussion here.)
In almost every way, [the classical world] is unspeakably cruel, to our way of thinking....
[Paul’s portion of the New Testament] is not a very lengthy amount of writing, but compacted into this very, very small amount of writing was almost everything that explains the modern world.... Concepts like international law, for instance, concepts of human rights, all these kind of things—ultimately, they don’t go back to Greek philosophers; they don’t go back to Roman imperialism; they go back to Paul. His letters, I think, are, along with the four Gospels, the most influential, the most impactful, the most revolutionary writings that have emerged from the ancient world....
I think of [Paul] as a kind of depth charge deep beneath the foundations of the classical world. It’s not anything that you particularly notice if you’re in Corinth or Alexandria. And then you start feeling this rippling outwards. And by the time you get to the 11th century in Latin Christendom, everything has changed. I think, essentially, what Paul’s significance is, is that he sets up ripple effects of revolution throughout Western history.... It spilled out so much, that now, in the 21st century, we don’t even realize where these ripple effects are coming from. We just take them for granted.
And of course, Paul’s ideas didn’t come out of nowhere. God began a process of transforming Paul’s world when He called Abraham out of his home country in order to create a new people who, over the centuries, would be shaped by God’s laws and His temple into a cultural foundation that would prepare the way for seeing and understanding Christ and His work. Paul’s writing was shaped not only by the contemporary reality of Jesus and His teachings, but also by the previous 1,500 years of a culture living under the Mosaic Law and writings of the Old Testament. Both Jesus and the Old Testament were revelations of God.
Many people make the mistake of thinking Christianity is silly. It isn’t silly, because our God isn’t silly. And when you see the massive accomplishments His word brought about in this world, you start to get a glimpse of that.