Possible Clues:

• Person having no faith in what he is told
• At the robbery? I don't believe it!
• One with no faith in Panama (the isthmus)
• One denying existence of a god
• Denier of God? In death 'e is terrified!
• Isaac Asimov, notably
• That's a very loud, bright sort of a struggle
• He does not believe in a god
• Evangelist's target
• One who does not believe in existence of a god