[Logophile]

Rather than preach against the "evils" of Harry Potter, this minister should preach the grace, riches, and resources of Jesus Christ.

I think you are on the right track here. Burning books, or even speaking out against the alleged evils of Harry Potter, make Christians look ridiculous at best. Preaching -- and practicing -- faith, hope, and charity would have a much more positive effect.

[to the core]

Practicing the faith would inded have a greater impact. However, it is much easier to blame and burn a book than it is to submit your will to God to the point where you tell the truth, avoid lust, practice kindness, exchange generosity for greed, and forgive rather than seek revenge. Unfortunately, many sinners have found themselves in the hands of an angry church -- and it has little appeal.