It all comes down to this.
One bunch of people, let's call them The Possessors of the Absolute Truth, believe they and they alone know the absolute truth about certain self-selected things. These things primarily concern divine intervention of one sort or another. The only proof they have is that other Possessors of the Absolute Truth have maintained the same assertions in the past.
Another bunch of people, let's call them Searchers for Truth*, say words to the effect that we don't need these unverifiable assertions to live our lives, not in the slightest, and that until we have some actual proof we won't take these claims seriously at all. We may indeed ridicule these assertions if we feel like it.
The first lot only have such power and authority in the world as they do have because of a long history of violence, authoritarianism, corruption, hypocrisy and worse.
* I only used this last description to annoy the Possessors of Absolute Truth