So, What is cleansed, anyway?

The result of kipper being accomplished by the sin and guilt offerings is that the person can be forgiven—that is, he or she will not have to be cut off from the community. If a person is not forgiven or not cut off from the community, the person’s continuing presence in the community will continue to contaminate the sanctuary, resulting eventually in the withdrawal of the divine presence and favor. But the contamination remains on the sanctuary, not on the person, so there is no suggestion of kipper cleansing an individual of sin.—Walton and Walton, The Lost World of the Torah, 76