For I determined not to know any thing among you, save Jesus Christ, and him crucified.... And my speech and my preaching was not with enticing words of man's wisdom, but in demonstration of the Spirit and of power. 1 Corinthians 2:2-4.
It had been Paul's custom to adopt an oratorical style in his preaching. He was a man fitted to speak before kings, before the great and learned men of Athens, and his intellectual acquirements were often of value to him in preparing the way for the gospel. He tried to do this in Athens, meeting eloquence with eloquence, philosophy with philosophy, and logic with logic; but he failed to meet with the success he had hoped for. His aftersight led him to understand that there was something needed above human wisdom.... He must receive his power from a higher source. In order to convict and convert sinners, the Spirit of God must come into his work and sanctify every spiritual development.1The S.D.A. Bible Commentary 6:1084.
To Paul the cross was the one object of supreme interest. Ever since he had been arrested in his career of persecution against the followers of the crucified Nazarene he had never ceased to glory in the cross.... He knew by personal experience that when a sinner once beholds the love of the Father, as seen in the sacrifice of His Son, and yields to the divine influence, a change of heart takes place, and henceforth Christ is all and in all.
At the time of his conversion, Paul was inspired with a longing desire to help his fellow men to behold Jesus of Nazareth as the Son of the living God, mighty to transform and to save. Henceforth his life was wholly devoted to an effort to portray the love and power of the Crucified One.... The apostle's efforts were not confined to public speaking; there were many who could not have been reached in that way.... He visited the sick and the sorrowing, comforted the afflicted, and lifted up the oppressed. And in all that he said and did he magnified the name of Jesus....
Paul realized that his sufficiency was not in himself, but in the presence of the Holy Spirit, whose gracious influence filled his heart.... Self was hidden; Christ was revealed and exalted.2The Acts of the Apostles, 245-251.
From Conflict and Courage - Page 341