Simplicity is an example of an abstract noun. It is because
an abstract noun is a word to describe something that a person can’t use any
sensory functions in which simplicity is a way of having to describe someone
without having to use any functions.
His audience was mostly puritan as was the case in the 18th century. His audience was probably scared mindless because his sermons usually included scary and vivid description of suffering, hell, sins, the devil, which was all supposed to scare you into being a better christian.
