פירוש על כלים 22:7

שנים מחפויו – from the tablets that are made for sitting.

A chair, of which two seat boards were removed, this one next to this one: Rabbi Akiva says: it is susceptible to impurity; And the sages say that it is clean. If two adjacent seat boards were removed, one of the side ones and the middle one, Rabbi Akiva still considers it susceptible to impurity. One could sit on the side seat board. The other sages say that this is no longer considered a chair, and therefore it is clean.

רבי עקיבא מטמא – But the Halakha is not according to Rabbi Akiba.

Rabbi Judah said: so too if the seat boards of a bride's chair were lost, though the receptacle under remained, it is clean, since where the primary function has ceased, the secondary one also ceases. Rabbi Judah relates back to mishnah four. There Bet Shammai and Bet Hillel disagreed with regard to a bride's chair whose seat boards were removed. Bet Hillel held that such a chair is clean. Rabbi Judah adds to this. The chair is clean even if the receptacle that they make under the chair to hold various things remained. Since the chair cannot be used in its normal fashion, for the bride to sit upon, the fact that it can be used for other purposes does not mean that it is still susceptible to impurity.

ונשתייר בו בית קבלה – that is slightly hollow and appropriate to receive pomegranates is pure, and we don’t defile it because it has a receptacle.

מפני שבטל העקיר – for is made for the primary purpose of sitting and not as a receptacle , for since the primary purpose was nullified, and on whose account it was considered a vessel, the secondary purpose was annulled, but it was not nullified for the reason that it has a receptacle. And this is the Halakha. And this is taught above in the chapter “Who takes apart/loosens” (Tractate Kelim, Chapter 19, Mishnah 10) and in the chapter “Mattresses and Pillows” (Tractate Kelim, Chapter 20, Mishnah 2).