What actually transforms a person who believes the gospel — the preaching of the cross, or something else?
The preaching of the cross—the gospel—is what literally transforms those who believe. Through the foolishness of preaching, God opens understanding that the One who died two thousand years ago answers the sin problem and imparts eternal life. It is nothing else; it is faith plus nothing.
Les teaches that many coming under the teaching suddenly realize it is an act of God that opens understanding that the One who died 2,000 years ago was the answer to the sin problem and can impart eternal life. He explains that through the foolishness of preaching—the preaching of the cross, the preaching of the gospel—it will literally transform those who believe. Nothing else. Faith plus nothing. He contrasts this with the Jews who require a sign and the Greeks who seek wisdom, saying Paul does not pay attention to either, but preaches Christ.