So he bought a bottle of cough medicine and decided that the next person who coughed would get a teaspoon full .The following Sunday someone coughed so he stopped preaching and gave the person a teaspoon of medicine and whispered in his ear. The person then got up and walked out.
This went on until the church was almost empty.
After the service the dominee asked the preacher what he said after giving the congregation medicine that resulted in a empty church.
The preacher said all he said was "For Cough"