And the man whose hair is fallen off his head
That is, from the back part of his head, from the crown of his head toward his neck behind: he [is] bald;
in that spot of the head where the hair is fallen off; and it denotes such a baldness as is occasioned by that, for it signifies one that had hair, but it is fallen off; whereas the baldness after spoken of is thought by some to be of such who never had any hair; though others will have it, that this intends a person bald all over; but it seems plain from what follows, that it designs one whose hair was fallen off behind, and was bald on that part only; and it may be observed, that this is only said of a man, not of a woman, because, as Aben Ezra remarks, she has much moisture in her, and therefore her head does not become bald; hair being like to grass, which flourishes in moist places: [yet is] he clean;
from the leprosy, or from the scalls, as Jarchi observes, because he is not judged by the signs of the head and beard, which are the place of hair, but by the signs of leprosy in the skin of the flesh, i.e. by the raw flesh and spreading.