In 1 Corinthians 1:18-2:16, Paul shows the heart of his message was that God sent his son into the word to die on the Cross in order to provide atonement for sin. To a Jew, Greek or Roman living in the first century, almost every word of this familiar summary of the Gospel would be radical, strange, or even foolish. A god cannot die, and he certainly would not die by crucifixion. What God did through Jesus runs counter to both Jewish and Gentile expectations about how gods are supposed to behave, or what the God of the Hebrew Bible does. The Gospel has some awkward facts, the object of our worship was executed as a criminal of the worst kind! In fact, he intentionally allowed himself to be destroyed in the most shameful way possible.
Paul does not shy away from these inconvenient facts of the Gospel in order to gain more converts because God has chosen foolish things in order to make foolish the wisdom of this world. The Gospel is not the sort of thing a religious person would have invented in the first century.
The Cross divides all of humanity into two groups, those who are “perishing” and those who “are being saved.” Perishing (ἀπόλλυμι) is a strong word chosen to highlight the present judgment of those who have rejected the Cross. The word used in the Septuagint for a sacrifice that is completely consumed in fire (Lev 7:10, for example). It is used for God’s judgment of the unrighteous (Sodom, Gen 18:24, several times). Psalm 2:12 used the verb for God’s destruction of the nations that have challenged the Lord’s anointed. The verb is in the present tense, indicating these people are under God’s judgment now because of their rejection of the cross.
Paul describes himself and his readers as “those who are being saved,” emphasizing the presentness of salvation. The verb is again in the present tense, all people are either (at this moment) either in need of salvation because they reject the Cross or being saved by the power of the Cross.
This division in humanity is based on the reaction to the Cross. The Cross is foolish to the ones who are perishing. Two related nouns (μωρία, 1:18 and μωρός, 1:27) refer to some idea that is senseless to believe, perhaps with the sense of ridiculous (the earth is hollow and lizard people are controlling our thoughts; a child telling a story about fairy tale creatures to a genius scientist, etc.) To believe in something foolish is a waste of time, since it cannot possibly be true.
Why is the Cross foolishness? In the Greco-Roman world, self-sacrifice was not considered a virtue. The idea a person might willingly shame themselves by voluntarily sacrificing themselves on a Cross is unthinkable and so radically offensive no rational person could believe it.
To those who are being saved, the Cross is the power of God. A death on the Cross was such an offensive and shameful death that it would have been shocking for Paul call it the “power of God for salvation.” D. A. Carson suggested the analogy of someone today claiming the Holocaust was “the power of God” (The Cross and the Christian Message, 12). No one in the world today would say the Holocaust is “the power of God.” Such a statement would be a jarring and offensive statement. Anyone making that sort of claim would not just be laughed at, but vilified and persecuted for such a claim.
Yet this is what Paul claims, because God chooses foolish things in order to silence the wise. He quotes Isaiah 29:14, a saying embedded in a context of the judgment on Judah for worship with their lips but not their heart (29:13); since their hearts are not right they are about to face God’s judgment. The Corinthians may have heard this as a pronouncement on the wise of this age (which is true), but since the object of God’s wrath in Isaiah Judah, it is possible Paul’s point here is that the church is also going to be silence because of their foolishness!
How does this “foolishness” play out in the modern preaching of the Gospel? Some American evangelical Christians like to use apologetics to present faith in Jesus as rational and reasonable to a rational mind. Others try to use secular culture to present the Gospel in a way which appeals to the modern, or post-modern mind (those “Mars Hill” ministries, for example). Would Paul have created a rational argument for the prove the need of the violent death of Jesus on the Cross? Would he have hosted a poetry slam in one of his churches for people to express their repressed feelings about religion? How can we “embrace the foolishness” and still reach our culture?