Understanding the nature of religious juridical subjects is one of the effective necessities of religious jurisprudence in making clear the religious precepts criteria. Both cleanliness and uncleanness are very important issues in the religious jurisprudence that understanding their nature from real and not real points of view may cause some basic changes in the field of cleanness and uncleanness. Now the question is whether cleanness and uncleanness are considered as real issues or nominal issues, what are the necessities and consequences of both views? Researching of the received religious percepts in the field of cleanness and uncleanness indicated that despite of lack of vividness in the nature of cleanliness and uncleanness from the viewpoint of real or nominal because of explicit reference of religious percepts criteria in the cases these proofs considered from high potential in proving and extracting of reality of cleanliness and uncleanness. The researcher not only considered the religious percepts in the field of cleanliness and uncleanness but also studied the criteria for religious percepts and concluded that cleanliness and uncleanness are a real affair which can be a matter of nominal religious percepts, and in that religious speeches they did consider cleanness and uncleanness for all things with attention to the real presence of both.