Keilim 10:7-8

Keilim 10:7

Let’s say that an old oven was inside a new one and a board was over the mouth of the old one. If removing the old one would cause the board to fall, the contents of both ovens are susceptible to ritual impurity; if it wouldn’t fall, everything is insusceptible. If the new oven was inside the old oven and the board was over the mouth of the old oven, then if there wasn’t a handbreadth of space between the new oven and the board, everything in the new oven is insusceptible to ritual impurity.

Keilim 10:8

Let’s say that pans were placed one inside the next with all of their rims level. If there was a sheretz (vermin) in the topmost or bottommost pan, only that pan is rendered unclean; all the others remain ritually clean. If the pans were punctured with holes through which a liquid would seep, then if the sheretz was in the topmost pan, they are all rendered unclean; if it’s in the bottommost pan, then that one is rendered unclean but the others remain clean. If the sheretz was in the topmost pan but the rim of the bottommost pan extended over it, then both are rendered unclean. If the sheretz was in the topmost pan and the rim of the bottommost pan extended over it, then any pan that has a dripping liquid in it is rendered ritually unclean.