And he shall look on the plague on the seventh day,.... To see whether there is any alteration in it in that space of time:if the plague be spread in the garment, either in the warp or in the woof, or in a skin, [or] in any work that is made of skin; the green and red spot be spread more and more in either of them, whether the colour remains the same or not, be changed, the green into red, or the red into green, yet if there was a spreading, it was a sign of leprosy.
According to the Jewish canon , if the plague was green and spread red, or red and spread green, it was unclean; that is, as Bartenora explains it, if it was red in the size of a bean, and at the end of the week the red had spread itself to green; or if at the beginning it was green like a bean, and at the end of the week had spread itself to the size of a shekel, and the root or spread of it was become red;the plague [is] a fretting leprosy; according to Jarchi, a sharp and pricking one, like a thorn; which signification the word has in Eze 28:24.
Ben Gersom explains it, which brings a curse, corruption, and oldness into the thing in which it is; an old "irritated, exasperated" leprosy, as Bochart , from the use of the word in the Arabic tongue, translates it:it [is] unclean; and the garment or thing in which it is.
Misn. Negaim, c. 11. sect. 3, 4. In ib. Hierozoic. par. 1. l. 2. c. 45. col.