John Gill Commentary Leviticus 13:15

"And the priest shall look on the raw flesh, and pronounce him unclean: the raw flesh is unclean: it is leprosy." — Leviticus 13:15 (ASV)

And the priest shall see the raw flesh
Or when he sees it, the person being brought to him to be viewed:

and pronounce him to be unclean ;
or shall pronounce him to be unclean:

[for] the raw flesh [is] unclean ;
made a man so in a ceremonial sense; (See Gill on Leviticus 13:10);

it [is] a leprosy ;
wherever any quick raw flesh appears in a swelling.