In school I was taught that Expository is the way to go, but with exceptions of coarse one of which being evangelism. The advantage to expository is the Bible is being revealed accurately, where sometimes topical can be way out of context while verses being cherry picked. However I am aware of those that disagree with this style and I wish to hear their argument and why they defend topical preaching. I heard a sermon from someone yesterday whom 35 minutes into his message finally read a verse, but the rest of the message was about himself and his stories and illustrations but he did not explain the text very well at all. This type of message disgusted me, yet there was those whom defended it as being revive style preaching.