1 Corinthians 1:18, 21, 23
1 Corinthians 1:18 ESV
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 Corinthians 1:21 ESV
For since, in the wisdom of God, the world did not know God through wisdom, it pleased God through the folly of what we preach to save those who believe.
1 Corinthians 1:23 ESV
but we preach Christ crucified, a stumbling block to Jews and folly to Gentiles