Taken from John MacArthur's Sermon: "Why I'm Committed to Expository Preaching."
1. A failure to do expositional preaching usurps the authority of God over the soul: If you don’t open the Word of God and let them hear the message of God, you have usurped His authority. God has a right to speak to men and women, has a right to speak to His church and when His church gathers, it is to hear Him speak...not you.
2. It usurps the headship of Christ over His church
3. A failure to preach and teach expositionally hinders the work of the Holy Spirit: The Spirit uses the Word as the means of sanctification. So if you fail to proclaim, to teach, to exposit the Word of God, you usurp the authority of God, you usurp the headship of Christ, and hinder the work of the Holy Spirit
4. A failure to do expositional preaching demonstrates then pride and a lack of submission, pride and a lack of submission.
5. A failure to do expositional preaching severs the preacher personally from the regular sanctifying grace of Scripture: Week by week by week by week exposition of Scripture calls for week by week by week intense study of the text. They’re concerned about reaching the culture and identifying with the culture and they know all that’s bad and they’re intimately acquainted with what’s bad in the culture...that’s toxic.
6. A failure to do expositional preaching, biblical, doctrinal exposition removes spiritual depth and transcendence from worship: If you’re superficial and you’re shallow in your preaching, your people think superficially and therefore they worship superficially.
7. A failure to do expositional preaching prevents the preacher from fully developing the mind of Christ critical to His work: Physicians of the soul diagnose with a divine diagnosis and cure with a divine cure. If you’re not biblically expert, then you’re not fulfilling your responsibility. It’s not about style, and you know that. It’s not about being cute and funny and clever, creative and innovative and attractive and winsome and charismatic, it’s about truth, and it’s about knowing the truth and being consistent and having facility with the truth and speaking the mind of Christ on that.
8. A failure to do expository preaching depreciates by example the spiritual duty of personal Bible study: If it is not demonstrated from the pulpit that there is a serious commitment to regular and intense examination of Scripture, how do you convince the people in the pew that it’s important? But if it’s more important for you to be clever or insightful, or psychological or anything else, you cannot convey that to the people
9. A failure to do expositional preaching prevents the preacher from being the voice of God on every issue of his time: Wherever you are, whenever you have an opportunity, you want to be the voice of God.
10. A failure to do expositional preaching breeds a congregation that is weak and indifferent to the glory of God and Christ. A failure to preach Scripture redirects people from a God-centered perspective to a man-centered perspective. It tends to undermine confidence, of course, in Scripture.
11. A failure to do Bible exposition robs people of their only true source of help. It robs people of their only true source of help, the Scripture.
12. A failure to do biblical exposition produces an attitude of indifference toward divine authority.
13. A failure to exposit the scriptures lies to people about what they really need: Treating people’s wounds superficially? They think they’re getting spiritual help and they’re not.
14. It strips the pulpit of power: You’re gone and the people are under the authority of the Word of God. And they want to be wounded and they don’t want to be wounded superficially. They want to be cut deep. When you don’t exposit the Word, you strip the pulpit of its power.
15. A failure to do expository preaching assumes that the preacher can change people by his ability: Don’t tell me what you believe, show me by what you do when you get in the pulpit.
16. A failure to do expository preaching reduces the preacher’s words to the level of everyone else’s word: So when you don’t exposit the Word of God, you reduce your own words, void of Scripture, to the level of everyone else’s words.
17. A failure to do expository preaching portrays an attitude of self-love rather than loving the Lord with all your heart, mind and soul.
18. It creates a destructive disconnect between doctrine and life: You give people superficial ideas about God, they are superficially motivated. So you create a destructive disconnect between sound doctrine and life. Life always imitates theology.
19. A failure to do expositional preaching denigrates the person of God by omitting those attributes and truths of his revelation that trouble and terrify the unregenerate. How would you define the Seeker Movement, the Emerging Church Movement that seeks to be inoffensive, right? And you denigrate the full glory of God by omitting those attributes and those truths of His revelation that trouble and terrify sinners.
20. A failure to do expositional preaching reduces the preacher to the level of every rival teacher shorn of authority. It leaves ministry success to be determined by who is most clever, who can get the biggest crowd.
21. A failure to do expositional preaching emasculates the dominion of the pulpit over people’s minds and souls.
22. A failure to do expository preaching disconnects people from the legacy of the past from the history of the church: But if you had no interest in the deep things of Scripture, you have absolutely no connection to those people and so you disconnect yourself from the great legacy of the past, the history of the church, the doctrines, the illuminating work of the Holy Spirit on those great men of the past.
23. A failure to do expositional preaching removes protection from error and carnality so dangerous to the church: If you feel the pain when God is dishonored and if you feel the pain when you’re people sin, then you’re going to do everything you can to lead them down the path where that’s not going to happen.
24. Failure to do expositional preaching abandons the duty to guard the truth: “What’s the biggest problem in the church?” Lack of discernment. You know, it’s spiritual AIDS. And people have a deficient discernment system can die of a thousand heresies.
25. A failure to do expositional preaching denies defacto all spiritual blessings from one’s relationship to the Lord: And our relationship to Christ develops along the line of understanding, loving, embracing, obeying truth.
26. A failure to do Bible exposition generates shallow, selfish prayer...shallow, selfish prayer. No deep communion.
27. If you don’t do expositional preaching, you fail to lead people to self-denial, cross-bearing humility.
28. A failure to do expositional preaching cheats people of the means to truly delighting in the Lord: Shallow knowledge means shallow love. As you go through your life and as you study the Scripture year after year, after year, after year, it’s so awesome, it’s so stunning, it’s so staggering, it’s so consistent, it’s so powerful