If the Mishna refers to a festival, what difference does it make where the key was lost. Carrying is not prohibited on a festival? The Mishna is not complete and should read thus: If one put it into a cupboard, which he locked and then lost the key, the Erub is nevertheless valid, providing it was a festival. On Sabbath, however, it is not valid. If the key was subsequently found, whether in the city or in the field, the Erub is nevertheless not valid. R. Eliezer, however, said: If it was found in the city, the Erub is valid, because he holds to R. Simeon's opinion, who said, that all the courts and wood-sheds in the city are as one ground and the key could be brought through them; but if found in the field it could not be carried.
Rabba and R. Joseph both said: "Our Mishna treats of a wooden cupboard and the Tana who holds that if the key was lost, the Erub was valid, considers the cupboard the same as a vessel which may be taken apart on the Sabbath and the Erub taken out, while R. Eliezer considers the cupboard the same as a tent which must not be taken apart on the Sabbath." How can they differ as to its being a vessel or a tent? If it was large all agree, that it is a tent, and if it was small all agree, that it is a vessel? Therefore Abayi and Rabha both say, that the Mishna treats of a case where the key was tied to the lock by a string, which could not be undone by hand. The first Tana holds according to R. Jose, that all vessels may be handled on the Sabbath for any purposes whatever (hence a knife used for cutting bread may be used to cut the string), whereas R. Eliezer holds according to the opinion of R. Nehemiah, who decrees, that all vessels may be handled on Sabbath only for the purposes for which they are intended.
MISHNA: Should the Erub roll (or be moved) out of the limit of the Sabbath distance, should a heap of mould fall on it, or should it be burned, or if the heave-offering (used for the Erub) became unclean, and any or all of this take place while it is yet day (i.e., before the Sabbath set in) the Erub is not valid. If it take place, however, after dusk (when it is already Sabbath) the Erub is valid. If the time when it took place is doubtful, R. Meir and R. Jehudah both say: This is (like driving) an ass and (leading) a camel (meaning, that a man is hemmed in on all sides). R. Jose and R. Simeon say: A doubtful Erub is valid? R. Jose further said: Abtolymus attested upon the authority of five elders, that a doubtful Erub is valid.
GEMARA: Said Rabha: (If the Erub rolled outside of the limit of the Sabbath distance) for a distance of over four ells it is not valid; but if it rolled for less than four ells, the man who deposited the Erub is allowed four ells to move in, outside of the limits, consequently the Erub is valid.
"Should a heap of mould fall on it," etc. At a casual glance it was assumed, that the Erub could have been extracted from under the heap of mould by hand, and accordingly the Mishna was in conformity with the opinion of Rabbi, that at twilight such acts as are prohibited by rabbinical law on account of the Sabbath-rest may be performed; subsequently, however, the conclusion was arrived at, that the Mishna is in accordance with Rabbi's opinion, and that the Erub in this instance could not be extracted by hand but by means of a hoe.
It was necessary to insert both clauses (concerning the rolling of the Erub and its being buried beneath a heap of mould) in the Mishna and for the reason; that, were the first clause only inserted, one might say: "If the Erub rolled out beyond the limits, it was no more in its place and hence it is invalid; but if it was simply buried beneath a heap of mould it is still in its proper place and why should it not be valid?" If the latter clause only had been inserted, one might say: "In this case the Erub was buried and could not be seen, hence it is invalid, but if it merely rolled out and can be seen, the same wind might bring it back, why should it not be valid?" For this reason it was necessary to mention both cases.
"Or should it be burned, or if the heave-offering (used as an Erub) became unclean," etc. The ordinance referring to an Erub which was burned up is taught in order to show the firmness of R. Jose, who declares, that (if a doubt existed whether the Erub was burned before or after dusk) although the Erub is no longer in existence, it is still valid, and the ordinance referring to heave-offering which became unclean was taught to show the firmness of R. Meir, who maintains that although the heave-offering was still there and only a doubt existed as to whether it became unclean before or after dusk, the Erub is nevertheless invalid. Is it possible, that R. Meir holds a doubtful case based upon rabbinical law to necessitate the more rigorous decision? R. Meir holds, that the law pertaining to Sabbath-limits is biblical. Does R. Meir indeed hold thus? Have we not learned in a Mishna further on (Chapter V., Mishna 3), that R. Meir maintains, when measurements are made to determine the Sabbath-limit and mountains are encountered that it is permitted to cut straight through the mountains (in an imaginary sense or figuratively speaking), and such subterfuges are certainly not allowed where biblical laws are concerned?
The latter opinion while credited to R. Meir is not in reality his own, but the opinion of his teacher, while the former is his own conviction and the proof is, that the Mishna quoted states distinctly: R. Dostai ben Janai said: I have upon the authority of R. Meir, etc.
We have learned in a Boraitha: How should the dictum of R. Jose to the effect, that "a doubtful Erub is valid" be explained? Thus: If an Erub was made with heave-offering concerning which there was a doubt whether it became unclean while it was yet day, or after dusk, or with fruit concerning which there was a doubt whether the tithes had been acquitted while it was yet day or after dusk, it constitutes a doubtful Erub, which is nevertheless valid; if, however, the Erub was effected with heave-offering concerning which there was a doubt whether it was clean or unclean to commence with, or with fruit concerning which there was a doubt whether tithes had been acquitted at all, it does not constitute a doubtful Erub, which is valid.
Let us see! Why is it said, that heave-offering, concerning which there was a doubt whether it became unclean before or after dusk, would constitute a doubtful Erub which was nevertheless valid, because the heave-offering is presumed to be in its original condition and that was certainly clean, why should not the same case apply to the fruit concerning which there was a doubt, whether tithes had been acquitted thereof or not, let the fruit also be presumed to be in its original condition and that is unseparated (of which tithes had not been acquitted)? Do not say, therefore, that the fruit was doubtful as to its having been separated but say: there was a doubt whether it had not subsequently been mixed with other (unseparated) fruit before or after dusk.
R. Samuel bar R. Itz'hak asked of R. Huna: If there were two loaves of bread before a man, one of which was clean and the other unclean and he said: "Make an Erub for me with the clean loaf wherever it may be"; but did not know which was which. [If both loaves which were heave-offerings, were used in making the Erub; for if they were ordinary and even (ritually) unclean they may be eaten by an ordinary Israelite], what is the law according to the diverse opinions? According to R. Meir, who pronounced a doubtful Erub invalid in a case where the entire Erub would have been unclean, it may be said, that in this case, where one of the loaves was positively clean, he may hold the Erub to be valid; or according to R. Jose, who pronounces a doubtful Erub valid in a case where if it is clean, he can distinguish it, it may be said, that in this case the Erub, would in his opinion be invalid because although part of it is clean, he cannot distinguish it from the unclean?
R. Huna answered: According to both R. Meir and R. Jose, when the Erub is deposited (while it is yet day) it must be fit to eat and in this case it could not be eaten to commence with, because, the clean could not be distinguished from the unclean, how then could an Erub be made therewith?
Rabha asked of R. Na'hman: If a man say: "This loaf of bread is to-day ordinary but to-morrow it shall be consecrated. Nevertheless make me an Erub therewith." What is the law? (Does it become consecrated at twilight and, as it is not permitted to make an Erub with consecrated things, it is not valid as an Erub, or does it become consecrated after twilight?) "The Erub is valid," was the answer. What is the law, however, if the man say: "To-day this loaf is consecrated, but tomorrow it shall be ordinary (i.e., it shall be redeemed by a sum of money representing its value); nevertheless make me an Erub therewith?" "The Erub is not valid," was the answer. What is the difference between the two cases? Said R. Na'hman to Rabha: "If thou wilt measure a whole Kur of salt and present me with it, 1 I shall tell thee the answer: If the loaf of bread was ordinary when it was deposited as an Erub, the fact, that at twilight it becomes