To the Jew, the gospel preaching a crucified Messiah was a stumbling block to acceptance of the message of the cross. They could not accept a conquering King that was crucified. That was a ridiculous notion to the Jewish person. The cross was a symbol of shame and suffering and besides the Messiah was to come to free them from Roman oppression. To the Gentile, the message of a crucified King as being the Savior of the world was folly and thus hindered their acceptance. A Roman god would never be crucified, so how can we accept a lesser god? In both cases, wisdom, not from God but from the world, was the ultimate barrier that kept both Jews and Gentiles from accepting the gospel. Paul states that the gospel does not require words of eloquent wisdom because that would empty the cross of its power (1 Corinthians 1:17). The gospel must stand on the power of the cross alone. That is where our redemption comes from, the cross and the blood shed on Calvary. The Jewish person could not see that the Messiah did come to free them from oppression, this oppression was due to their sin and redemption through the cross was the answer.
Today, first through modernism and now postmodernism, we rely on wisdom obtained through study. We think we have all the answers and have no need of a God that requires so much of us. I do not have time to read the Bible, pray, and besides, I like living my life this way. Who are you to say that it is a sin? We rely more on the government than we do on God. They will protect us, what can God do? To the secular world, the word of the cross is folly. However, this is the part of this world that is perishing.
“For the word of the cross is folly to those who are perishing, but to us who are being saved it is the power of God” (1 Cor 1:18, ESV).
“And even if our gospel is veiled, it is veiled to those who are perishing” (2 Cor 4:3, ESV).
“and with all wicked deception for those who are perishing, because they refused to love the truth and so be saved” (2 Thess 2:10, ESV).