This excerpt is from the blog back in April 2008. Phil explains how to rightly understand and apply Paul's discourse at Mars Hill to the idea of contextualization.
[T]here is an obvious and legitimate need to speak a language people understand if you want to reach them. Paul didn't go into Athens and speak Hebrew to the Areopagites. He spoke Greek. There's nothing the least bit remarkable about that. What Paul did not do was adapt his message to suit the basic values and belief systems of that culture.
Observe what he did do. Every dyed-in-the-wool contextualizer will tell you that he quoted the philosophers' favorite poets right back at them. "For in Him we live and move and have our being, as also some of your own poets have said, 'For we are also His offspring'" (v. 28). He quoted two well-known Greek poets in quick succession. Epimenides, a poet from the island of Crete in the sixth century BC, wrote the line, "In Him we live and move and have our being." And Aratus, a Macedonian poet from the third century BC, wrote "we are also His offspring." Two lines from poets who were already ancient in Paul's lifetime.
Epimenides and Aratus weren't exactly the Lennon and McCartney of 1st-century Athens. Paul was not embracing aspects of the first-century Greek worldview or culture just to relate with the Athenians; he was not affirming something just because he wanted to seem hip and this poetry was fashionable in the Greek academy of his own day. Quite the opposite. He was quoting from their ancient literature to express his own worldview. His point was that these were truths about God that their own ancient ancestors once recognized also. Common grace had made these truths obvious (Romans 1:19), but the Athenian intellectuals had suppressed them. In other words, those quotations from the literature of their forefathers actually confronted the more contemporary and popular worldview of that generation.
As a matter of fact, Paul was doing his utmost to demolish their worldview, so he went systemically through a list of ideas they held in error, and he confronted them with true ideas instead.
There he stood in Athens, amid countless temples and idols. Talking to the culture's most enlightened minds, all of whom held worldviews that were for all practical purposes atheistic, materialistic, and superstitious all at once. Half of them (the Stoics) believed in an afterlife, but it was a disembodied, spiritual notion of the afterlife. The other half (the Epicureans) were such hardened materialists that they believed when the body died and the molecules went back to dust, that was it. By their way of thinking, there was no such thing as a human soul and thus no conscious existence after death.
It begins to look like Paul was deliberately trying to provoke them. And in a true sense he was. He caps the sermon in verse 30 with a demand for repentance. And believe me: that was no less offensive on the Areopagus in the first century than it would be in the UN general council today. Paul could have hardly packed more hard truth and counter-cultural commentary into those few words. Every sentence Paul said had something in it that would be offensive to those philosophers.
Now, it should be obvious that in the sense postmodern evangelicals use the term, Paul was not contextualizing the gospel in order to reach these philosophers with a message that would sound friendly, comfortable, and easy for them to embrace.