Paul tells us in the fifth chapter of the book of Galatians that those who are unclean will not inherit the kingdom of God. What is uncleanness though? According to the 1828 Webster's Dictionary uncleanness means several different things. First, uncleanness is "foulness; dirtiness; filthiness." Foulness is defined as "Offensive to the senses; revolting; Having a bad odor or taste; rotten or putrid; containing dirt, impurities, or other foreign matter." Dirtiness is defined as "Covered or marked with dirt or an unwanted substance." Filthiness is defined as "Covered or smeared with filth; disgustingly dirty." All of these are essentially in the physical sense. Obviously it does not seem Paul was referring to the physical sense of uncleanness although I would recommend remaining clean in this sense in order to not be "revolting" to other people's sense of smell.
Two other definitions for uncleanness according to Webster's are "Moral impurity; defilement by sin; sinfulness" and "Lewdness; incontinence." These definitions are what Paul is really referring to. Let's consider these in more detail.
