The application in a sermon is like the end of the spear. That is, if you want to kill people. But the purpose is not to thrust the text into their arteries until they bleed out; the purpose is to make them want to embrace the text with all their heart and obey it. This is a heart change that takes place over sustained exposure to God's Word.
The eternal consequences of a sermon take shape in a world we cannot see. In this invisible world, the word of God quickens the heart of those who are being sanctified by the Holy Spirit of Jesus Christ to be made more like Him. If we miss this, we miss the point of preaching, no matter how pointed our application. So, perhaps in a real desire to see visible results of this invisible work, we rush to the application too soon. This leads to an application-driven approach to preaching.
The application-driven approach to preaching suggests that real life-change is the goal of preaching, and thus we should, as quickly as we can, get to the application of the text. When not handled well, however, this can lead to superficial exegesis that moves quickly to the "bottom-line" of behavior. My ultimate goal is not to change behavior. I am not a priest. I am not a cleric. My function in the preaching of scripture is to be a conduit through which truth flows toward the larger goal that God has for this person—to be made into the image of Christ.
Now, we are in fact trying to change lives. But ultimate life-change does not happen with a change in immediate behavior. Ultimate life change comes in exposure to the living words of God. This will change lives over time.
Granted, this desire for ultimate life-change often leads to another extreme—preaching with no application. The idea behind this approach is that the Holy Spirit applies the text to the heart, so no application at all is needed. The problem here is that it requires a preacher to be so stimulating that the attention of the congregation will be sustained throughout a sermon that may become a lengthy exercise in exegesis. Another liability is that people could conclude that listening is enough; i.e., they really do not feel the pressure to do anything as a result of what they have heard.
Clearly, we want to avoid being application-driven, and on the other hand we should avoid skipping application all together. We want to be text-driven preachers who illuminate how the text interfaces with life.
So, toward the goal of stirring us up by way of reminder (2 Pet. 1:12), here are some ways to keep our applications sharp.
1) Be faithful.
The application point to press is the one within the text and its immediate context. We do not read the text looking for application points per se. This may turn the word into a veritable moral code for good behavior. We are not dispensing advice like a kindly grandparent. We are proclaimers of a truth that sets people free, a freedom that is won at the price of exposing them to scripture. So find and emphasize first the originally intended application.
2) Put the application in its place.
Application may come throughout the sermon or all at the end. How the text develops will determine this, and there is no right or wrong. Assuming that each point should have a certain amount of application may force false application on a more doctrinal/expositional text. Consider the genre—narrative, poetry, dense doctrine, epistle—and plan the application accordingly.
3) Remember the trajectory.
The application may move from the general to the specific. For example, one could make the case for the sanctity of life from Psalm 139:13, 14. If we are "fearfully and wonderfully made . . ." then this general truth can be applied to the specific issue of abortion. However, the opposite is also true.
Application may move from the specific to the general. As evidenced in the admonition in Titus 3:9-11 that the pastor must avoid silly controversies and confront the sinning brother, God generally wants order in local congregations. This move from the specific to the general is helpful because it allows us a way to take seemingly very specific issues in the text and pan out to show how they contribute to the whole picture.
This is the most important aspect of application, and no doubt the hardest to communicate. What we are advocating is using the illustration of the sermon and the application as one unit by weaving the illustration into the application.