The Torah commands a woman to bring korbanot after the birth of a child. A son is to be circumcised on the eighth day of his life. The Torah introduces the phenomenon of tzara'at (often mistranslated as leprosy) — a miraculous affliction that attacks people, clothing and buildings to awaken a person to spiritual failures. A kohen must be consulted to determine whether a particular mark is tzara'at or not. The kohen isolates the sufferer for a week. If the malady remains unchanged, confinement continues for a second week, after which the kohen decides the person's status. The Torah describes the different forms of tzara'at. One whose tzara'at is confirmed wears torn clothing, does not cut his hair, and must alert others that he is ritually impure. He may not have normal contact with people. The phenomenon of tzara'at on clothing is described in detail
"The Kohen shall look, and behold! The affliction has covered his entire flesh — then he will declare the affliction to be pure." (13:13)
Tzara'at, frequently mistranslated as leprosy, was a disease caused by spiritual defects, such as speaking lashon hara (slander). (Nowadays we are on such a low level spiritually that our bodies do not reflect the state of our spiritual health in this way.)
The verse here is puzzling, for if "the affliction has covered the entire flesh" of the person, this must mean that he is far from pure, and yet the Torah tells us that the Kohen shall "declare the affliction pure.” How can he be pure if the affliction covers his whole body?
The answer is that he is so far from being cured, having ignored all the warnings to do teshuva (repentance), that the disease ceases to perform any further purpose. Therefore, the Torah specifically says not that the Kohen shall declare him pure, but rather that "the affliction is pure." But he, on the other hand, is as far from purity as is possible.
- Based on the Ha'amek Davar and Rabbi S. R. Hirsch