Negative Mitzvah 308
It is forbidden to tamper with signs of Tzara'at
Deuteronomy 24:8 "Take heed in the plague of Tzara'at"
This Negative Mitzvah forbids a person to tamper with or remove signs or spots of Tzara'at from his body.
He must follow the guidelines of the Torah and do as the priest instructs (see above Negative Mitzvah 307).
Negative Mitzvah 307
It is forbidden to shave a spot of "Tzara'at" on the skin
Leviticus 13:33. "But the patch shall not be shaved"
At times, even our bodies can become affected because we sin.
The Torah describes a skin disorder which can appear on a person's body as a result of his misdeeds.
This skin disorder is called "Tzara'at" (see Positive Mitzvah 77).
The Torah declares that Tzara'at is an impurity that a person has brought upon himself, causing the holiness within him to be hidden.
Since this is not a regular skin disease, a doctor's check-up will not help. Only the priest is knowledgeable and capable of defining purity and impurity.
The priest inspects the Tzara'at and instructs the afflicted person what he must do while he is impure.
Of course, he also helps him do Teshuvah for his sin, because that is the real reason for his skin disorder.
The actual "Tzara'at" spot must not be removed or shaven.
This Negative Mitzvah commands us not to remove any hair growing on that spot.