1 Corinthians 2:4-5

Amplified Bible

⁴ And my message and my preaching were not in persuasive words of wisdom [using clever rhetoric], but [they were delivered] in demonstration of the [Holy] Spirit [operating through me] and of [His] power [stirring the minds of the listeners and persuading them], ⁵ so that your faith would not rest on the wisdom and rhetoric of men, but on the power of God.