Purity in Leviticus finds its opposite most starkly in death itself, and leprosy is the disease most closely resembling death and decay. For this, stringent laws are given on how to handle leprosy, and to receive miraculous healing of it is exceptionally meaningful. This makes Naaman's healing in 2 Kings 5 all the more potent, as his turning from the gods of Rimmon to rather worship the LORD is just as much a life-saving act.