. Wood — enough to build a threshold. R’ Yehudah says: Enough to make a ‘‘sandal’’ behind the threshold. Clay — enough to put between the cracks. Walls of a feeding trough and partition walls do not become tamei from negaim. Jerusalem and outside the Land [of Israel] do not become tamei from negaim.

[The Kohen] does not go into his [own] house to confine, nor [does he stand] inside the house that contains the nega to confine. Rather, he stands next to the entrance of the house that contains the nega and confines, as stated: ‘‘And the Kohen shall leave the house to the entrance of the house, and he shall confine the house for seven days.’’ He returns at the end of the week and examines [the house]. If it spread, ‘‘and the Kohen commands that they remove the stones that have the nega and throw them outside the city to a tamei place. And they shall take other stones to replace the [removed] stones, and he shall take other clay and plaster the house.’’ He does not take stones from this side [of the house] and build them into the other side; nor [does he take] clay from this side and build [it] into the other side, nor [does he take] lime. Two [stones] are not replaced with one [stone], nor one [stone] with two, but two, three, or four [stones] can be replaced with two. From here they said: ‘‘Woe is to the evildoer and woe is to his neighbor.’’ Both [owners] remove [the afflicted stones], scrape [around them], and place the [new] stones. However, he alone brings clay, as it is stated: ‘‘And he shall take other clay and plaster the house.’’ His neighbor does not assist him in the plastering.

[The Kohen] returns at the end of the week to examine [the house]. If [the nega] returned, ‘‘The house is demolished — its stones, its wood, and all the clay of the house — and removed from the city to a tamei place.’’ An adjoining expansion [of] any size is tamei; a distant one must be the size of a gris. The return of a house nega must be two gris.

There are ten houses: [If the nega] turns dull after the first [week] or [it] disappears, it is scraped off and [the house] becomes tahor. [If the nega] turns dull after the second [week] or [it] disappears, it is scraped off, and the house requires taharas hatzipporim. [If the nega] spreads after the first [week], [the owner] removes, scrapes, and plasters, and [the Kohen] gives [the house] a week [of confinement]. [If the nega] returns, [the house] is demolished. [If the nega] does not return, [the house] requires taharas hatzipporim. [If the nega] remains the same after the first [week] and spreads after the second, [the owner] removes, scrapes, and plasters, and [the Kohen] gives [the house] a week [of confinement]. [If the nega] returns, [the house] is demolished. [If the nega] does not return, [the house] requires taharas hatzipporim. [If the nega] remains the same after both [weeks], [the owner] removes, scrapes, and plasters, and [the Kohen] gives [the house] a week [of confinement]. [If the nega] returns, [the house] is demolished. [If the nega] does not return, [the house] requires taharas hatzipporim. If the nega reappears before [the owner] made [the house] tahor with taharas hatzipporim, [the house] is demolished. If [the nega] reappears after [the owner] made [the house] tahor with taharas hatzipporim, [the house] is examined anew.

A cornerstone [which the owner] is required to remove must be completely removed. But when he [is required to] demolish it, he demolishes his [side] and leaves his neighbor’s [side]. This results in a stringency in the removal [of the stones] over the demolition [of the house]. R’ Elazar says: A house built with a main support and smaller materials [where the nega] appears on the main support, [the owner] is required to remove all of it; [where] it appears on the smaller materials, he removes his [side] and leaves his neighbor’s [side].

[If] a house on which a nega appears has an upper story, the beams are considered part of the upper story. [If the nega] appears on the upper story, the beams are considered part of the lower story. [If] there is no upper story, [the house’s] stones, wood, and clay are demolished with it, but not the roof-tiles [lit., the rectangles] and the lattices of the windows. R’ Yehudah says: The frame built on top of [the lower story] is demolished with it. Its stone, wood, and clay render tamei as long as they are the size of an olive. R’ Elazar Chisma says: As [small as] they are.

A confined house makes [a person] tamei from within, and a confirmed [house makes tamei] from within and without. Both make tamei upon entering.

If someone builds a tahor [building, using stones] from a confined [house], and [then] nega returns to the house, he must remove the stones. [If nega] returns to the stones, the first house is demolished and the stones function as an indicator for the second house.

When a house extends over an afflicted house or a tree extends over an afflicted house, someone who enters the outer one is tahor, these are the words of R’ Elazar ben Azariah. Said R’ Elazar: If one of its stones renders tamei upon entering, the house itself should certainly render tamei upon entering.

[If] someone tamei is standing under a tree and someone tahor passes [underneath the tree, the tahor person] becomes tamei. [If] someone tahor is standing under a tree and someone tamei passes [underneath, the tahor person] remains tahor. If [the tamei person] stops, [the tahor person becomes] tamei.

[If] a tahor person put his head and most of his body into a tamei house, he becomes tamei. [If] a tamei person puts his head and most of his body into a tahor house, he makes it tamei. A tahor garment of which three by three [fingerbreadths] were put into a tamei house becomes tamei. [If someone] put an olive-sized piece of a tamei garment into a tahor house, the house becomes tamei.

If someone enters an afflicted house with his garments on his shoulder, and his sandals and rings in his hands, he and they become tamei immediately. [However, if] he is wearing his garments, his sandals, are on his feet, and his rings are on his fingers, he becomes tamei immediately but [the garments, sandals, and rings] remain tahor until he stays enough time to eat a halfloaf of wheat bread, rather than barley bread, while reclining and eating it with a condiment.

Someone stood inside [an afflicted house] and extended his hand outside with his rings on his fingers. If he remained long enough to eat a half-loaf, [the rings] become tamei. Someone was standing outside and extended his hand inside [an afflicted house] with his rings on his fingers, R’ Yehudah renders tamei immediately, but the Sages say: Until he remains long enough to eat a half-loaf. They said to R’ Yehudah: ‘‘When his entire body becomes tamei, his clothes do not become tamei until he remains [in the house] long enough to eat a half-loaf; is it not logical that when he himself does not become tamei, his clothes should not become tamei either until he remains [in the house] long enough to eat a half-loaf?’’