A minister that doesn't believe in God reminds me of a Democrat that doesn't believe in government.
These aren't ministers. They are con men.
They may be con men or they may simply be occupying a job. I see the unbeliever ministers much like union auto workers. They don't really believe in the work they do or in the results. They're just there and keep on going.
But when they don't believe in anything, then what is there to get excited about? There is no literal Presence. The Holy Spirit is just a concept. Jesus may or may not have actually lived, but he was just a pretty good man with occasional bouts of temper. No difference between Jesus and Buddha or Mohammed, really.
How can you be excited about anything when nothing really matters and everything is symbolic at best?
Satan has his shoes off and his feet on the desk. His work is being carried on by a number of believers, but more unbelievers. After all the devil doesn't require that you believe in him, just that you do what he will.