I Corinthians 2

4 And my speech and my preaching *2 Pet. 1:16were not with persuasive words of human wisdom, *Rom. 15:19; 1 Cor. 4:20but in demonstration of the Spirit and of power, 5 that your faith should not be in the wisdom of men but in the *Rom. 1:16; 1 Thess. 1:5power of God.