Answer Life Lesson

The טומאה of a מצורע is so severe, that he must leave the community and be alone, secluded even from other people who are טמא, and even from other people who have צרעת.

Therefore, the one who declares the person to be a מצורע, which causes him to be banished from the community, must be a כהן.

The כהן’s role is to bless Yidden, and to do so with love (as they say in the ברכה before נשיאת כפים, that Hashem commanded them לְבָרֵך אֶת עַמוֹ יִש ְרָאֵל בְאַהַבָה).

The כהן, as an אִ ישׁ הַ חֶ סָ ד, will be sure not to exclude a fellow Yid from the community unless it is absolutely necessary. This is why the תורה entrusts him with this responsibility.

(Of course, he will subsequently do all he can to bring about the טהרה of the מצורע as well).