How can the the rabbis decree that Trumah which is Tahor M'doraissa should be burnt because of a ficticious tumah that they created?
Yisroel Stein, Monsey, NY
This is what the Kollel replied to a similar question in the past
Best regards, M. KORNFELD
How could chazal introduce a gezeriah to burn terumah that is not "really" tameh in some case. Since it is prohibited to burn terumah that is tahor chazal are overriding a Torah law with a positive act (kum va-aseh).
Kol Tuv,
Eli Turkel
There is no prohibition to burn Terumah. The reason why Terumah may not be burned (or destroyed in some other fashion) is because of the Mitzvas Aseh to properly guard Terumah ("Mishmeres Terumosai," Bamidbar 18:8). The requirement to properly guard Terumah applies only when the Terumah can be eaten. When the Terumah cannot be eaten -- such as when the Rabanan decree that it is Tamei and forbidden to be eaten -- it may be burned.
M. KORNFELD
How can the the rabbis decree that Trumah which is Tahor M'doraissa should be burnt because of a fictitious tumah that they created?
Yisroel Stein, Monsey, NY
(a) This is what I wrote to a person who asked this question some 15 years ago:
"There is no prohibition to burn Terumah. The reason why Terumah may not be burned (or destroyed in some other fashion) is because of the Mitzvas Aseh to properly guard Terumah ("Mishmeres Terumosai," Bamidbar 18:8). The requirement to properly guard Terumah applies only when the Terumah can be eaten. When the Terumah cannot be eaten -- such as when the Rabanan decree that it is Tamei and forbidden to be eaten -- it may be burned."
(b) However, I am not completely satisfies with my answer. The Gemara tells us (16b) about Halachos that were included in the Takanah d'Rabanan that allows glass vessels to become Tamei "lest people accidentally burn Terumah and Kodshim for such a Tum'ah". This implies that it is a terrible thing - i.e. an Isur Torah - to burn Terumah and Kodshim even when they have become prohibited from eating due to contact with a Tum'ah mid'Rabanan.
The only way to reconcile this with what I wrote is by suggesting the Tum'ah d'Rabanan of glass vessels is different from the Tum'ah d'Rabanan of Eretz ha'Amim. In the former, the Takanah only considered them Tamei l'Chatchilah, i.e. we cannot let them touch Terumah. But if they touched Terumah the Terumah may still be eaten, b'Di'eved.
However, I am not at all sure that this is a viable possibility.
(c) Another possibility is that the Rabanan "uprooted the laws of the Torah" in an active manner, and allowed us to burn Teruamah, as per the Gemara in Yevamos 90. However, if this is true then the Gemara there (which tries to prove that the Rabanan have such power) ought to have cited it as an example of such practice.
So we are back to looking for an answer to your question.
Best regards,
M. Kornfeld
If "mishmeres terumosai" doesn't apply to Terumah that can't be eaten, then why do some of the tannaim in Massekhet Terumos and Pesachim Chapter 1 think that it's forbidden to add tum'ah to Terumah that's already temei'ah?
Avie Walfish
I believe those sources are discussing Terumah Teluyah (i.e. Safek Tamei). If the Tum'ah is only b'Safek, it is still possible, theoretically, for it to become permitted (if the Safek is resolved). Therefore some hold that the Terumah cannot be made Tamei intentionally.
Mordecai Kornfeld