What was the doctrine of the Lord that Paul preached?
Paul preached the doctrine of the cross—Christ crucified—declaring that Christ died for the sins of the world. He did not preach signs, miracles, or philosophy, but the preaching of the cross, which is foolishness to those perishing yet the power of God to those saved.
Les explains that Paul's doctrine was not the signs and miracles demanded by the Jews or the wisdom sought by the Greeks. Instead, Paul preached Christ crucified, and the preaching of the cross is foolishness to those who perish but the power of God to those who are saved. When the context speaks of the doctrine of the Lord having come from Paul's lips, it identifies it as “how that Christ died for the sins of the world.” Les notes that this theme pops up throughout all of Paul's letters, showing it was his consistent message.