Paul said in 1 Corinthians 2:1-8 And I, when I came to you, brothers, did not come proclaiming to you the testimony of God with lofty speech or wisdom. (2) For I decided to know nothing among you except Jesus Christ and him crucified. (3) And I was with you in weakness and in fear and much trembling, (4) and my speech and my message were not in plausible words of wisdom, but in demonstration of the Spirit and of power, (5) that your faith might not rest in the wisdom of men but in the power of God. (6) Yet among the mature we do impart wisdom, although it is not a wisdom of this age or of the rulers of this age, who are doomed to pass away. (7) But we impart a secret and hidden wisdom of God, which God decreed before the ages for our glory. (8) None of the rulers of this age understood this, for if they had, they would not have crucified the Lord of glory.
Again, Paul didn't come with this great ability to make moving speeches. His ministry was simply to teach the Word of God simply. That's all any preachers call is.That's comforting to me. My effectiveness isn't based on how articulate I am or how I have a deep, commanding speaking voice or how much education I have.
The Bible says in Zechariah 4:6 "Not by might nor by power, but by My Spirit says the Lord." Also in Hebrews. 4:12 says, "For the word of God is living and active and sharper than any two-edged sword, and piercing as far as the division of soul and spirit, of both joints and marrow, and able to judge the thoughts and intentions of the heart."
That being said, the Word is alive and active. All that a pastor or teacher should have to do is give it to you!