I enjoy listening to the two classical music stations in Chicago, but when I'm getting my breakfast, I almost never tune them in because the sound from this clock radio is thin. So when I turn on the classical stations, I use my living room system, and I get thick, quadraphonic music with full bass and clear, sparkling treble. As superior as this system is to the clock radio, so Spirit-empowered preaching outdoes other communication. As Christian preachers, our words are qualitatively different than other forms of communication. As we speak spiritual words, our listeners experience revelation and illumination from the Holy Spirit within their human spirit, touching them at the marrow of their being.
Preachers engage parts of the person that mere media can never reach.
Now, this is no excuse for anemic communication, because preaching is a divine and human event. To use an extreme example, even if God empowers my sermon, someone who doesn't understand my language will profit but marginally. Neither will someone who sleeps through my sermon or is distracted by a crying baby or who daydreams. And so it is if my message is confusing or boring. A sermon that bores today would likely have bored the saints two thousand years ago.