1 Corinthians 2:2-5

"For I resolved to know nothing while I was with you except Jesus Christ and him crucified. And I was with you in weakness, and in fear, and in much trembling. And my speech and my preaching [was] not with enticing words of man's wisdom, but in demonstration of the Spirit and of power: That your faith should not stand in the wisdom of men, but in the power of God."