What does 1 Corinthians 2:4 mean?

Paul continues to describe how he presented the gospel about Jesus Christ and the cross to the Corinthians when he first arrived in town. He did not put on an impressive display of speech and human wisdom, as some traveling teachers of their day were known to do. In fact, Paul wrote in the previous verse that his time with them was marked by weakness, fear, and trembling.

Now he emphasizes once more that his presentation and the message itself were not delivered with persuasive words of wisdom. In other words, he did not dazzle them with impressive arguments in order to convince them to believe in Jesus. Instead, he brought the simple message of Christ and the crucifixion with a demonstration of the Holy Spirit's power.

What was this demonstration of power? What did the Corinthians experience that helped them to believe the message of the gospel? That is not explicitly revealed here, but it was how God showed the Corinthians that Paul's teaching was backed by His undeniable power. The fact that this did not come as a result of some emotional, theatrical display was further proof that Paul's message was true, and not merely a cleverly-crafted sales pitch.