Paul agrees with the Corinthians that his message is lacking in cool rhetorical flourishes that the Greeks esteemed. He is proud that it centers upon the cross–even though the Corinthian culture deems it fit for the fool rather than the cool (v. 18, 22). Paul will accept such a conclusion—but only when the terms are clarified. The message of the cross might be “foolish”—but only to those who are perishing because they have rejected the deliverance of God. It is foolish in the same way that a fireman is foolish to those who would rather die inside a burning house than be rescued.
Isaiah 29 is called in as exhibit A (v. 19). The setting has to do with Judah’s dullness and spiritual blindness during the time of Hezekiah (29:9-10). The reason for it is their heart was far from God (v. 13). They thought they were “safe” because after witnessing Assyria’s conquest of the northern kingdom (Israel), they struck up an agreement with them (see 28:14-15 where it is referred to as a “covenant of death,” because it was made with a nation who could bring death to them). For good measure, they also made an alliance with Egypt, so that if Assyria turned on them, they could fall back on Plan B. They didn’t have to trust in Jehovah—they had made their own plans! They could take care of themselves. They were self-sufficient. Of course, it didn’t work out that way. Sennacherib and the Assyrians surrounded Jerusalem and Judah was saved, not by the Egyptians, but because God intervened (Isaiah 37). So much for Judah’s “wisdom!”
As it was in the time of Judah, so it was in Paul’s time. Following the wisdom of the world had led to their lost condition (1:21). Their heroes, their wise men (people like Socrates, Plato, and Aristotle), had not brought them closer to God. That came through only through what they regarded as foolish (v. 25). So much for their “wisdom!” The church must never lose sight of the fact that the best thing we have going for it is Jesus Christ. It is not our strategies, our methods, or our abilities. It is Him and Him alone. If He is the power and wisdom of God (v. 18,24,30), then why would we look to anything else?