The problem is when pastors do this, particularly when they are well-known, is that when they are inevitably wrong, it repels the very people we have been commanded to make disciples of:
Matthew 28:19
19 Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,
These unsaved and those in the world point to guys like Hagee and say: “You believe this guy?!? Why would I want to be like that?”. It hurts our witness. Hagee’s prophecy will end up being skewered as a comedy spot on Jon Stewart, and will serve to harden the hearts of those who need most the gospel.
Better he simply preach the Word, feed the hungry, clothe the naked, and help those in need. Believers should not be in the prediction business.
Some will need even these things to finally turn and confess Jesus the messiah.
Prediction business? Even we are in the prediction business to some degree...would you not agree? Jesus is coming. Jesus will step foot on the mount of olives. The rapture will happen in a blink of an eye. There will be war and rumor of war. In the end times, good will be called evil and evil good.
Scripture is really all ya need. No one needs to predict anything, it is all spelled out in the bible. These are very exciting times. Only those who deny God should fear these times....problem is, they don't know it. How will they know it? Who will help them see the imminent time of the return of our messiah?
Prophecy has it's place.