Klawans helps distinguish the concepts of holy, common, pure, and impure, often radically misinterpreted in Christian circles. According to Klawans, there are three distinct characteristics of ritual impurity:
- The sources of ritual impurity are natural and more or less unavoidable.
- It is not sinful to contract these impurities
- The impurities can convey an impermanent contagion to people and to many items within close proximity.