Leviticus 14:37

“And he shall look on the plague, etc.] That which is taken or suspected to be one, being pointed unto by the owner of the house: and, behold, [if] the plague [be] in the walls of the house; for there it chiefly was, if not solely; and from hence Gersom infers that it must be a walled house, and that it must have four walls, neither more nor fewer; and with this agrees the Misnah f512, according to which it must be four square; the signs of which were, when it appeared, with hollow strakes, greenish or reddish, which in sight [are] lower than the wall: these signs agree with the other signs before given of leprosy in men and garments; the first, the hollow strakes, which are explained by…”

“This section is separated from that on leprosy in clothing Leviticus 13:47-59 with which it would seem to be naturally connected, and is placed last of all the laws concerning leprosy, probably on account of its being wholly prospective. While the Israelites were in the wilderness, the materials of their dwellings were of nearly the same nature as those of their clothing, and would be liable to the same sort of decay. They were therefore included under the same law. I put the plague - Yahweh here speaks as the Lord of all created things, determining their decay and destruction as well as their production. Compare Isaiah 45:6-7; Jonah 4:7; Matthew 21:20. Leviticus 14:37 Hollow strakes ... -…”

“In the walls of the house - This was an extraordinary judgment of God peculiar to this people, either as a punishment of their sins, which were much more sinful and inexcusable than the sins of other nations; or as a special help to repentance, which God afforded them above other people; or as a token of the mischievous nature of sin, typified by leprosy, which did not only destroy persons, but their habitations also: Hollow streaks - Such as were in the bodies of leprous persons. Leviticus 14:40”

“14:37 If the mildew extended deeper than the wall’s surface it was more serious than if it were just on the surface. The same idea was expressed by “more than skin-deep” in the examination of infected individuals (see study note on 13:3).”

“Lev 13:3, Lev 13:19, Lev 13:20, Lev 13:42, Lev 13:49 Leviticus 14:38”

“If the leprous spot appeared in "greenish or reddish depressions, which looked deeper than the wall," the priest was to shut up the house for seven days. If after that time he found that the mole had spread on the walls, he was to break out the stones upon which it appeared, and remove them to an unclean place outside the town, and to scrape the house all round inside, and throw the dust that was scraped off into an unclean place outside the town. He was then to put other stones in their place, and plaster the house with fresh mortar. Leviticus 14:43”