Though Romans 1-2 and 1 Corinthians 9 establish the basis and motive for contextualization, no single biblical text is more helpful on the subject of contextualization than 1 Corinthians 1:22-25, which provides the basic formula for doing contextualization: ... Here Paul assumes the mixed nature of culture. He tells us that when he spoke to Greeks, he confronted their culture's idol of wisdom. ... To the Jews, a salvation that came through a crucifixion was weak and ineffective. ... Notice, however that while the gospel offended each culture in somewhat different ways, it also drew people to see Christ and his work in different ways. Greeks who were saved came to see that the cross was the ultimate wisdom—making it possible for God to be both just and the justifier of those who believe. And Jews who had been saved came to see that the cross was true power. It meant that our most powerful enemies—sin, guilt, and death itself — have been defeated. ... Paul's approach to culture, then, is neither completely confrontational nor totally affirming. He does not simply rail against Greek pride in intellect and Jewish pride in power; instead he shows them that the ways they are pursuing these good things are ultimately self-defeating. He reveals the fatal contradictions and underlying idolatry within their cultures and then points them to the resolution that can only be found in Christ. This is the basic formula for contextualization. [Tim Keller, Center Church: Doing Balanced, Gospel-Centered Ministry in Your City (Grand Rapids, MI: Zondervan, 2012), 111-2]
We have seen in the earlier quote by Iain Campbell which deals with Tim Keller's interpretation of Romans 1. It is reproduced below:
For all Keller's discussion of biblical narratives, however, it is difficult to agree with him that Paul's basic thesis in Romans 1 is that idolatry is the basic human problem, the soil out of which every sin grows. It could be argued that this is to reverse the Pauline argument, which is that unrighteousness, or sin, leads to a suppression of the knowable truth about God, which in turn is expressed by creature worship instead of by Creator worship. For Paul, the idolatry is the symptom, not the cause. [Iain D. Campbell, "Keller on 'Rebranding' the Doctrine of Sin," in Iain D. Campbell and William M. Schweitzer, eds., Engaging with Keller: Thinking Through the Theology of an Influential Evangelical (Darlington, England, EP Books, 2013), 43]
As Campbell showed, Keller's skill as an exegete doesn't seem to be great, and here as he attempts to exegete 1 Corinthians 1, we see once again that Keller misses the point of the text.
The main error Keller makes is to assume that this is Paul laying out his strategy for witnessing of the Gospel. Rather, when one looks at the context, the passage is a polemic loudly trumpeting the "foolishness" of preaching and the "foolishness" of the cross. In other words, if one wishes to see a "strategy" here by Paul, Paul accentuates how foolish and weak the Gospel message is, then claim that it is precisely IN the "weakness" and "foolishness" that the power and wisdom of God is found. How Keller manages to turn a polemical text into an instruction manual is beyond me, for surely the two are different genres altogether!
Secondly, we note that what stumbles Jew and Greek is the manner of how God provides salvation: the death of Christ on the Cross. Jews expected a Messiah to triumph in battle over their enemies, not die in shame and under a curse. Greeks see the notion of God coming in the flesh as foolishness, and the death of Christ appalling. God's way of salvation goes against how they think God should have acted, and thus they stumble. The stumbling block here is the Cross and how the different cultures interpret it, NOT as Keller puts it, what they idolize. The Greeks for example do not idolize wisdom, but rather athlete stature and youth. Greek "wisdom" or philosophy informs their conceptual world. The Jews also do not idolize power, but rather they expect power because of their interpretation of the Messianic prophecies given in former times. The problem for both Jew and Greek mentioned here is an inability to conceive the notion of the Cross, and has nothing to do with their respective idolatries.
So, when Keller states that Paul "does not simply rail against Greek pride in intellect and Jewish pride in power," nothing can be further from the truth. There are no "contradictions" revealed, but rather a mere statement that Jewish and Greek unbelievers are in fact wrong. Instead, it is they that are "weak" and "foolish," the "foolishness of God" being wiser than the wisdom of Man and the "weakness of God" stronger than Man's strength. What we have in 1 Corinthians 1 is an apologetic confrontation, not a dialogue and definitely not a witness strategy.
1 Corinthians 1 in conclusion is not a text about contextualization. It is a polemical text, an apologetic text. Keller's interpretation is thus an eisegesis of the passage, altering its plain sense in service to his over-arching idea of "contextualization."