Látszólag már Toszfot említi besém Szifrá, hogy táhor. Rámbán mégis misztápék (és Su"Á is ezt paszkenolja). Miért? Áh"S máárich a témában (15-20), Grá szintén.
It is questionable whether it is permitted to lay a ladder on the roof so that the schach can be placed upon it. RAMA: Therefore, we do not put schach on it. Even laying it on the schach in order to hold it in place is forbidden. This is the law for any object that is susceptible to ritual impurity, such as a bench and a chair that receive midras uncleanness (Maharil).
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4) (Vayikra 11:32): "vessels of wood": I might think (to include) a ladder, a rack, a tray, and a lamp. It is, therefore, written "of … wood," and not all wood. Or I might think (to exclude) a table, a tavla, and a dolfaki (also kinds of tables). It is, therefore, written "all … wood," for inclusion. Why did you see fit to include these and to exclude these? After Scripture included, it excluded. It is, therefore, written "sack." Just as sack is distinct in serving both man (He can clothe himself in it) and his servers (He can put his vessels in it), so I include table and dolfaki, which serve man (He can support himself on them) and the servers of man (He can place his vessels in them), and I exclude ladder, which serves man but not the servers of man, and (I exclude) rack, tray, and lamp, which serve the servers of man, but do not serve man.
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