The Kohen plays a pivotal role in the tumah and taharah, contamination and purity, of the metzora. Horav Meir Yechiel, z.l., m’Gustinin offers a profound explanation for the Kohen’s significance in this process. Realistically, when we rebuke the slanderer for his disparaging tongue, he is quick to respond, “But, I am only telling the truth.” He is justifying his iniquity with a spurious display of virtue. This false righteousness is an integral part of the slanderer’s trade. He conceals his evil with a facade of piety.
This is why we bring him to the Kohen. The Kohen is a descendant of Aharon, the rodef shalom v’oheiv shalom, who loved peace and pursued peace. Aharon was “also” pious; he would never lie – unless it was in the course of bringing about peace among people, harmony between husband and wife. He felt it is permissible to alter the truth “slightly,” if it is in the pursuit of shalom. Aharon’s idea of a falsehood was to tell each one of the individuals involved that the other one wanted to make peace. This generated a feeling of remorse and shame in the other fellow. They eventually made up. This was Aharon’s “lie”.
The Torah insists that the slanderer, who claims he is saying the truth, should come to the Kohen who, at times, is prepared to tell a falsehood to help promote unity. If the Kohen, who sometimes bends the truth, says the slanderer is tamei, he is tamei b’emes, truly tamei.