Two things that are admired and idolized in our culture are strength and to have something make sense. When something does not make sense it is thought to be merely foolish and of no lasting good. If something appears weak it is despised and rejected out of hand for the same reason.
But God chose what is foolish in the world to shame the wise; God chose what is weak in the world to shame the strong;
(1 Corinthians 1:27 ESV)
God indeed demonstrates his strength by holding all creation together only by his desire to hold it together. He has mercy on all people by curbing our impulses to consume each other. He also limits the calamity that can befall us from our surrounding environment and even our own bodies due to disease.
The greatest example of God’s strength comes in the crucifixion of our Lord. This is done in weakness in order to supply eternal life to all. But this appears to be weakness to the eyes of unbelief that need and admire strength. The Creator of heaven and earth is a victim of a huge injustice on the cross. This is foolish to the wise one. It is foolish to think the crucifixion of one man has anything to do with forgiveness of sin. Only faith can see Jesus was there strongly and wisely carrying the burden of the sin of all.
Jesus has instituted what appears to be weak and foolish means of grace to deliver the fruit of his cross to the sinner: A man proclaiming the guilt we all share for falling short of the glory of God, then proclaiming forgiveness in the name of Jesus saves us.
Then he opened their minds to understand the Scriptures, and said to them, Thus it is written, that the Christ should suffer and on the third day rise from the dead, and that repentance and forgiveness of sins should be proclaimed in his name to all nations, beginning from Jerusalem.
(Luke 24:45-47 ESV)
The weakness of having the words of Jesus flowing into our ears, and that those words will save us seems ridiculous to those outside of Christ. There is nothing flashy like bright lights and lots of noise, only the loving words from Jesus that our sins are forgiven for his sake.
This belief has fallen on hard times in the Church. Proclamation of the Gospel has been replaced by hints for happy living. Sermons now include a whole list of things that have nothing to do with salvation. Suggestions on how to go out there and become successful at all sorts of endeavors. All things from financial well-being to information on how to win a debate with other believers is touted as a Gospel. The Gospel is also said to include an ever increasing holiness in life. Yes, a believing one in Jesus will seek to live holy. Financial success is desirable. These things, although admirable from human points of view, will not save.
Only the preaching of our guilt before God for what we have done and left undone will lead to repentance and the forgiveness of sin. Due to our falling short of the glory of Christ we live in constant need of repentance and the forgiveness of sin. This is provided to us by the cross of Jesus and delivered to us through the proclamation of the Gospel.