The belly of the whale is a dark place where one is slowly dissolved by a greater force and that is the only sign evil will get. Why were they evil? That is a relative equation and a partial truth for the wise to ponder. They were evil because instead of asking for a sign they should be taking a sign as God is already giving them signs. One only has to look and see. From there they will know what to do to foster the Kingdom, hearken, Amen?