In the days of the Beis Hamikdash [Holy Temple], Tzaraas [a spiritual ailment similar to leprosy] was inflicted on those who transgress in certain areas, including that of loshon hara [slanderous speech. A Kohen would then declare the individual spiritually impure, followed by a week of quarantine. The Torah says that then “The Kohen shall look at it on the seventh day and behold! – The affliction retained its color, and the affliction did not spread on the skin, then the Kohen shall quarantine it for a second seven day period. The Kohen shall look at it again on the seventh day, and behold! – if the affliction has dimmed and the affliction has not spread on the skin, then the Kohen shall declare him pure it is a mispachas he shall immerse his garments and become pure” (Leviticus 13:5, 6).
The Sforno (verse 5) emphasizes that this sequence is illogical. The requirement that spiritual contamination and purity of the affliction be dependent on the declaration of a Kohen is a rule without logical reason in the Torah, “For the lips of the Kohen shall guard knowledge.” When the blemished individual comes to the Kohen, he will teach him or her to do teshuva [mend their ways] and to pray for themselves. The Kohen will also pray for them. (Click here for Hebrew text)
The Sforno observes that the more logical assumption would be that a blemish on one’s body should be inherently pure or impure; why should it depend on the declaration of a Kohen? It either is or isn’t Tzaraas. However, G-D made it dependent on the declaration of a Kohen in order that the afflicted person be required to go to a Kohen and be taught how to cure himself through repentance and prayer, and have the Kohen also pray on his or her behalf.
Why did Hashem feel that the process should be done in this way? If a person suddenly fell ill and he began to experience a very painful rash on a part of his body, wouldn’t one think that he would run to the doctor for a cure? Even more so, if he was already diagnosed with a terrible illness, he would doubtlessly make a follow up appointment with the doctor!? The Kohen was the spiritual doctor of the day, and if a Jew was diagnosed with tzaraas by a kohen, wouldn’t he logically seek out, on his own, whatever means were necessary to cure himself, be it prayer, repentance, etc.? Indeed, this is especially so if it has been a week and he sees that nothing is changing. So why did the Hashem create a situation where the question of whether the blemish is contaminated or not is dependent on the word of the Kohen, and not obviously or automatically known?
It would seem that when it comes to healing one’s soul one would not be as quick to run to a “doctor” for a cure, despite knowing for a fact that something is wrong. Yet the state of insecurity and the unsettled feeling would drive him back to the Kohen, without hesitation, in order to properly learn from him how to mend his ways. Out of Hashem’s pure love and mercy for his children, He left it up to the kohen to declare a person contaminated and pure, in order that the person is guaranteed to get the proper means to heal him or herself.