“Now while Paul was waiting for them at Athens, his spirit was provoked within him as he saw that the city was full of idols. 17 So he reasoned in the synagogue with the Jews and the devout persons, and in the marketplace every day with those who happened to be there. 18 Some of the Epicurean and Stoic philosophers also conversed with him. And some said, “What does this babbler wish to say?” Others said, “He seems to be a preacher of foreign divinities”—because he was preaching Jesus and the resurrection. 19 And they took him and brought him to the Areopagus, saying, “May we know what this new teaching is that you are presenting? 20 For you bring some strange things to our ears. We wish to know therefore what these things mean.” 21 Now all the Athenians and the foreigners who lived there would spend their time in nothing except telling or hearing something new.” (Acts 17:16-21 (ESV)
Paul returns to reasoning with people, moved, provoked by the idols in the city. He ended up speaking with Epicurean and Stoic philosophers, who were the most prominent by this time. The stoics were more or less what we would call pantheists, yet without the trappings of your local crystal broker. They were strict moralists emphasizing self-control and a strong sense of duty and obligation. The Epicureans, get more or less a bad name these days, though I myself identify more with modern day epicureans than the ancient counterpart. They were crass materialists who sought to maximize the enjoyment of life through restrained, refined and carefully measured use of life’s goods. Epicurus himself pretty much lived like a hermit. This life was all they believed they had. YOLO, as it were. But this had the counterintuitive effect of enforcing moderation, rather than “living large.” Paul’s teaching would have been quite foreign to both schools of thought. But Paul would have been familiar with both as he entered this famous city. Paul knew Greek culture, he knew the places where he could find common ground from with to work from as he reasoned with the people in the town square.
Paul could, and often did, quote the Greek poets and philosophers. Because of this, some of it is now actually the word of God. But that is a rabbit hole I don’t want to go down right now. He would work from where they themselves were. To save the Greeks he would become a Greek, and relate the gospel to them. His desire, no matter how depraved the audience, was that of God’s that all men would be saved and come to the knowledge of truth.