What is the corollary between "ve'Yatza ha'Kohen el mi'Chutz la'Machaneh" and "ve'Huva el ha'Kohen"?
Rashi: Since the Metzora has to go to the Kohen in order to be declared Tahor, 1 the Kohen must go outside all three camps, 2 to wherever the Metzora is residing (or to a location just outside the walls [Seforno]), in order to be accessible to him. 3
Moshav Zekenim (citing Toras Kohanim): The verse implies that the Kohen was inside the Machaneh. This teaches that a Kohen Metzora cannot be Metaher another Metzora.
From which the Metzora was sent once he was declared a Muchlat (Rashi)\a] Moshav Zekenim implies that . Refer also to 13:46:2:1**.
And the Torah begins with "Vehuva el ha'Kohen to stress that when the Metzora wants to become Tahor has no option other than to do it via a Kohen (Ramban).