Earthenware ovens have dominated our study over the last week. These ovens are similar to earthenware utensils in that they contract tumah by the tumah being in its airspace, but not if the tumah came into contact with the outside of the kli. This is in contrast to keilim of other materials where the tumah is transferred only through direct contact. The novelty of an earthenware oven is that it is susceptible to tumah even if cemented to the ground.
The Mishnah (5:11) explains that if the oven was made of metal or stone, then it does not share the same (unique) laws as an earthenware oven. The stone oven is not susceptible to tumah (as with all stone vessels), whereas the metal oven is treated like any other metal kli.
The Tosfot Yom Tov cites the Torat Kohanim that derives this law from the pasuk, "Everything on which the carcass of any of them falls shall be tameh, an oven or stove shall be smashed..." Chazal understand that these unique laws only apply to an oven for which "smashing" applies. The Mishnah Achrona explains that while an oven made of any material can be smashed, that is not what the Mishnah is referring to. It is referring to materials for which smashing is the only means of purifying it, if it became tameh. Stone keilim are not susceptible to tumah, while metal keilim have other means of purification. For earthenware vessels, the only method of purification is breaking them.
What is worthy of note, is how the Rishonim explain the difference between the metal and earthenware oven. The Rash explains that the metal oven is different since it would not become tameh if the tumah is in its airspace, and if it did become tameh, then it can be purified by being immersed in a mikveh. The Rashash however asks that an additional difference should have been included -- the fact that the earthenware oven is susceptible to tumah even if cemented to the ground. Indeed the Rambam includes this difference in his explanation. Is there significance in the Rash's omission?
Rav Daniel Wolf, (Mincha Tahora, p210-213) believes there is, and it is connected to the Rash's and Ritva's different understandings of this particular law.
There are two ways to understand this law. The first is that the earthenware oven is unique. Unlike other keilim it does not have a base and is used specifically when attached to the ground. Nevertheless the Torah teaches that it is still defined as a kli and susceptible to tumah. In other words, the above cited pasuk, is novel in introducing a new class of kli that is also susceptible when attached to the ground. This is the understanding of the Ritva.
Another possible understanding is that the oven is not novel. A vessel is only considered tahor if the kli was attached from the outset. The oven was first constructed and then attached to the ground, and therefore susceptible to tumah.^1^
Rav Wolf suggests that this second understanding is the position of the Rash. When the Mishnah (2:1) teaches that wooden, leather and glass keilim that are flat are tahor, the Rash asks why earthenware keilim were not included in the list. The Rash answers that unlike other keilim that require a receptacle, to contain contents, earthenware keilim only require an inside for susceptibility to tumah. His proof is from the oven which does not have a base, but has an inside and is susceptible to tumah. By the Rash drawing on the oven, Rav Wolf suggests that the susceptibility to tumah of an oven is not a specialised subset of earthenware keilim but share all the laws of earthenware keilim in general. It is then possible to suggest that the fact that the oven is susceptible to tumah even when attached to the ground draws from a general law that applies to keilim -- it is defined as a kli prior to being attached to the ground.
Rav Wolf therefore suggests, that the omission of the Rash was intentional because it is not unique to earthenware ovens. This general law, that it is susceptible to tumah when attached to the ground would then apply to ovens of other materials.
^1^ Rav Wolf draws a parallel from the world of shechita, where despite the fact that if one used an object that is mechubar le'karka for shechita it would be invalid, if one took a knife and then attached it to the wall, the shechita would be valid (Chulin 16a).
Receive our publication with an in depth article and revision questions.
Listen to the Mishnah Shiurim by Yisrael Bankier
NEW: Full Mishnah Text and Commentaries
Kuntrus on Masechet Kinim (Updated: 2014/5774)