Kelim, Chapter Ten, Mishnah Six
1) If a jar had a hole in it and wine lees stopped it up, they protect it.
2) If one stopped it up with a vine shoot [it does not protect] until he plasters it at the sides.
3) If there were two vine shoots, [it does not protect] unless he plastered it at the sides and also between the one shoot and the other.
4) If a board was placed over the mouth of an oven, it protects if he plastered it at the sides.
5) If there were two boards [it does not protect] unless he plastered at the sides and also between the one board and the other.
a) If they were fastened together with pegs or with bamboo joints there is no need for them to be plastered in the middle.
Section one: This section goes according to the opinion of the sages in yesterday’s mishnah. The wine lees protect the jar from impurity because they form a tight seal from within.
Section two: In order for the vine shoot to count as a tightly-fitting lid, he must plaster it around from the sides.
Section three: If he closed it up with two vine shoots, then he must plaster it from both the sides and between the shoots in order for the shoots to be considered a tight seal.
Section four: A board, one that cannot become impure, can offer a protective seal to an oven, as long as he plasters it from the sides.
Section five: Similar to the case of the two vines, if he uses two boards, he must plaster in between them as well as at the sides.
However, if the two boards were fastened together with either pegs or joints, he need not plaster in between them for them to be considered a tight lid.