That's an impressive poster. That face! Usually the patent-medicine hawkers were a bit more cheerful, though; this fellow seems furious you're not using Dr. Parker's Fig Pangyric at this very moment.

The movie concerns a travelling vaudeville show that decides to go religious, and does the Elmer Gantry number, fooling the rubes. Eventually something bad happens, which forces the main characters to pray for real, and then their prayers are answered and everyone converts and the organ, I assume, plays something reverent and hymnal.