Soncino English Talmud
Bava Batra
Daf 66a
it is not liable to uncleanness where it is; and if one takes honey from it on Sabbath, he becomes liable for a sin-offering. The Sages, however, say that it is not on the same footing as the soil, that it cannot serve as a surety for a prosbul, that it can become unclean where it is, and that one who takes honey from it on Sabbath has not to bring a sin-offering'? — [It is not this statement either], for there [R. Eliezer's reason is] as reported by R. Eleazar, that we find written in the Scripture, And he dipped it in the honeycomb; [from which he reasoned that,] just as one who plucks anything from a wood on Sabbath becomes liable for a sin-offering, so one who takes honey from a comb on Sabbath becomes liable for a sin offering. It must be then the statement of R. Eliezer about the shelf, as we have learnt: 'If a baker's shelf is fixed in the wall, R. Eliezer says that it is not capable of becoming unclean and the Sages say that it is.' [We now ask again], which authority [does the statement adduced above follow]? If it is R. Eliezer, then even if the pipe was first hollowed and then fixed [the water from it should not render the mikweh unfit]: if it is the Rabbis, then even if it was first fixed and then hollowed, [it should still spoil the mikweh]? — It is in truth R. Eliezer, and he makes a difference in the case of flat wooden articles, because their uncleanness was decreed only by the Rabbis. It would follow from this [would it not], that [the rule about] 'drawn' water derives from the Scripture?
Sefaria
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