There are those who would suggest that preaching should be a purely cerebral activity, laying out Gods truth for people to understand clearly and make sense of. They might suggest that emotion plays no part in true preaching because emotional manipulation is dangerousand our goal as Christians is to present the truth clearly before all men.
In some ways I dont disagree with this sentiment, manipulation by playing on peoples emotions is a disgraceful thing and certainly has no place in true preaching. But to remove emotion altogether from your preaching is a knee jerk reaction and probably needs reconsidering. The gospel is not an intellectual exercise, it isnt something that can be dissected and presented as a series of undisputable facts. The gospel is completely rational and in line with our intellect, there is no leap of faith involved, but the gospel also touches our hearts and this is an essential part of preaching.
Giving someone a message which is entirely intellectual and in no way affects the heart means you have given someone a message which will in no way affect their lives. Preaching must deal in some way with the heart and emotions which are present in the Bible passage being dealt with.
On the flip side of that, preaching which is entirely emotional and carries very little intellectual weight is generally of the manipulative kind and will be too flimsy to have any lasting impact. Our hearts much be tethered by the truth, which is something we hold in our minds.