1 Corinthians 1:18 NKJV - "For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God."
Those believers who have sought to witness of the "power of the cross" find that many unbelievers can't accept the message about the cross as having any possible relevance to their lives. They just can't understand how a Man could die on a Roman cross and have such an impact on the world. They accept that someone can die as a hero by placing their lives in jeopardy to save someone else from suffering injury or death. But they hardly look at the cross of Christ as a death of a hero.
1 Corinthians 2:14 says in part, "...the natural man does not receive the things of the Spirit of God, for they are foolishness to him..." The unsaved mind of man, which, by the way, we who are saved possessed the same thing, that mind can't take spiritual truth and make sense of it. Why? Because unbelievers are "blinded" to the truth of the Gospel as 2 Corinthians 4:3,4 says, "But even if our gospel is veiled, it is veiled to those who are perishing, whose minds the god of this world has blinded, who do not believe..."
We preach a powerful message! But it takes the Power of God to break through the hardness of men's hearts to bring people to recognize the significance of Christ's sacrifice on the cross. In Jesus' ministry He dealt with his disciples' inability to cast out a demon as recorded in Matthew 17:14-21. When the disciples asked Jesus why they failed He told them in verse 21, "However, this kind does not go out except by prayer and fasting." In other words, Jesus was saying that we need to pray that the power of God would break the devil's power over the mind of men. I see this as asking God to "lift the blindfold" off people's minds and allow them to see the "sense of the Gospel." We who preach and witness must remember, our words can only go to the eardrums of the loss. It takes the Spirit of God to speak to the heart! May we rely on Him to bring people out of their foolish unbelief and see that only Jesus can save their souls.