We all deliver from the same warehouse, but the issue is delivery. You can know Greek and Hebrew and systematic theology, Old Testament, New Testament, until it is coming out of your ears but if you cannot put it on someone's front doorstep, it does not matter how much you know. In fact, your knowledge may be a hindrance to you.
To deliver the gospel effectively, you must know the difference between teaching and preaching. Many seminary graduates end up mimicking their seminary professors when they stand in the pulpit to preach. Yes, those professors were godly men, worthy of emulation. But they were not preaching, they were lecturing. And there is a world of difference.
Lecturing is tremendous in the classroom. It is dreadful in the pulpit.
A young man once asked Martin Lloyd-Jones the difference between teaching and preaching. Lloyd-Jones said, “Young man, if you have to ask me the difference between teaching and preaching, it is obvious that you have never heard preaching, because if you've heard it, you know the difference.”
Preaching stands on the shoulders of teaching and reaches higher. Preaching begins with teaching but goes beyond. And as you are preaching, there are certain elements of preaching: It involves elements of passion and persuasion.
As soon as I say persuasion people in reformed circles get their guards up and cry, “Manipulation!” We are so scared of Charles Finney that we think it is spiritual to be boring in the pulpit, that it is some high watermark of preaching if we can put people to sleep in the pew.
But persuasion is biblical. The Greek word peitho is used fifty-two times in the New Testament. In 2 Corinthians 5:11 Paul says, “Therefore, knowing the fear of the Lord, we persuade men.” We want to win people over to Christ. There is the cognitive doctrine, theology, exegesis that we present as evidence. We are putting the objective hard truth before the listener, but we are also persuading them to render the verdict. If we believe in the free offer of the gospel we must call people to respond to the truth of the word of God. When I asked my wife to marry me, I did not just do a word study of agape and phileo. I had to sell a (bad) product to her. I had to work to persuade her and that came from a place of passion not manipulation.
True biblical preaching has passion and has persuasion. From eye contact to hand gestures, it must be evident that your whole being is bringing this message, and that you are bringing it because there is deep conviction in your own heart. When the preacher takes the word of God seriously, the people begin to take the word of God seriously. And your convictions are contagious. They will spread like a fire from the pulpit to the pew.