Yevamot

— R. Judah follows his own view; for he stated:  The law of neutralization takes no effect in homogeneous objects.  [Had the piece] not been crushed, however, what [would have been the law]? Assumingly that it could not be neutralized! Why. then, was it taught. 'If, however, a piece of a levitically clean sin-offering was mixed up with a hundred pieces of clean and unconsecrated meat … neutralization cannot take place'?  Let the distinction be drawn in [the case of consecrated meat] itself, thus: This  applies only where it  was crushed; but when it was not crushed it may not be neutralized! — He preferred [to speak of] a mixture of clean with clean. According to Resh Lakish,  wherein lies the difference between the first clause and the final clause?  — R. Shisha the son of R. Idi replied: The first clause deals with uncleanness that was due to liquids,  which is only Rabbinical,  while the final clause [deals with a prohibition]  which is Pentateuchal.  What, however, [would be the law in the case of] uncleanness through a reptile?  Assumingly that no neutralization is permitted! Why, then, did he state in the final clause, 'If, however, a piece of levitically clean sin-offering was mixed up with a hundred pieces of clean and unconsecrated meat … neutralization cannot take place'?  Let the distinction rather be drawn in [respect of consecrated meat] itself, thus: This  applies only to uncleanness due to liquids, but when it is due to a reptile it may not be neutralized! — He preferred [to speak] of a mixture of clean with clean. Rabbah replied:  The first clause [deals with] a prohibition under a negative precept  while the final clause [deals with] one that involves the penalty of kareth.  But surely was it not Rabbah who stated that in all Pentateuchal prohibitions there is no difference  between a prohibition that is due to a negative precept and one that involves kareth!  — This is a difficulty. R. Ashi replied:  [The law  in the] final clause is due to the fact that [the consecrated food] is an object which may be made  permissible,  and any object which [in certain circumstances] becomes permitted  cannot be neutralized even in a thousand.  This statement of R. Ashi, however, is mere fiction.  For to whom [would the mixture become permitted]!  To  the priest it is permitted [all the time];  to the Israelite  it is for ever forbidden!  The statement of R. Ashi must consequently be regarded as mere fiction. But is R. Johanan of the opinion that terumah at the present time  is Pentateuchal?  Surely it was taught: If in front of two baskets, one of which contained unconsecrated fruit and the other that of terumah, were two se'ah measures, one containing unconsecrated fruit and the other that of terumah, and the latter fell into the former, behold these are permitted,  for it is assumed that the terumah fell into the terumah and the unconsecrated fruit fell into the unconsecrated fruit.  And [in reference to this ruling] Resh Lakish stated: 'Only if the unconsecrated fruit  was more than that of the terumah';  while R. Johanan stated, 'Even if the unconsecrated fruit were no more than the terumah'.  Now, according to Resh Lakish  the ruling  may well be justified since he may hold the opinion that with Rabbinically [forbidden food] also it is necessary  to have a larger quantity [of the permitted food]. According to R. Johanan.  however, a difficulty arises!  'This'  [R. Johanan may reply] 'is the view of  the Rabbis,