Zeh Vzeh Gorem

From Halachipedia

Food produced by materials that are forbidden are themselves forbidden since it is like one is benefitting from the original prohibition. When there are two contributing factors to the product, one that is forbidden and one that is permitted, it is called zeh v'zeh gorem (Heb. זה וזה גורם; lit. this and that cause it).

Zeh Vzeh Gorem

  1. Where there are two contributors to a production one which is permitted and one which is forbidden that is called zeh v'zeh gorem (Heb. זה וזה גורם; lit. this and that cause it). Generally, when each factor could not have independently created the result but together can do so it is permitted.[1] One explanation of this halacha is that it is similar to nullification.[2]
  2. If the forbidden factor makes its impact first and then the permitted one does, it is forbidden and not considered zeh v'zeh gorem. For example, if forbidden wood is used to used to fuel the beginning of the baking of bread but afterwards the forbidden wood is replaced with permitted wood, it is forbidden.[3]
  3. Items produced solely by a forbidden source are forbidden and there is a dispute whether it is rabbinic or biblical.[4]

Zeh Vzeh Gorem as It Applies to Specific Areas of Halacha

  1. Zeh vzeh gorem only applies to items that are forbidden from benefit and not things which are permitted in benefit and just forbidden for eating.[5] Additionally, it could apply to something which contributes a significant improvement to the result and changes it thereby. For example, trumah sourdough with non-trumah sourdough added to a dough is considered zeh vzeh gorem even though it isn't forbidden from benefit.[6]
  2. Zeh vzeh gorem for chametz is permitted according to most poskim,[7] though some hold it is forbidden.[8] A practical ramification of this is whether the milk of a cow that ate chametz on pesach is a product of chametz and other factors and is considered zeh vzeh gorem. Most are lenient.[9]
  3. Zeh vzeh gorem for avoda zara according to most is permitted,[10] while according to others is forbidden.[11]
  4. Zeh vzeh gorem for hekdesh is according to some permitted,[12] while according to others is forbidden.[13]
  5. Zeh vzeh gorem of a dvar sheyesh lo matirin is forbidden according to most opinions since zeh vzeh gorem is based on nullification and there is no nullification for a dvar sheyesh lo matirin.[14] Some dispute this point and permit it.[15]

Creating Zeh V'zeh Gorem Initially

  1. Zeh vzeh gorem is forbidden initially, however, if there would be a large loss to avoid it, it is permitted even initially. For example, an oven that was finished with forbidden fuel can now be used with permitted fuel since the baked products would be a result of forbidden and permitted fuel, which is zeh v'zeh gorem. Even though it is only permitted after the fact, the alternative of destroying the oven is a large loss and not necessary.[16]
  2. If a non-Jew created something with zeh v'zeh gorem it is permitted to buy it even initially.[17]
  3. Bread made over permitted fuel in a forbidden oven is permitted since forbidding the food would render the oven useless and that would involve a large loss.[18]
  4. Bread made over forbidden fuel in a permitted oven is forbidden. Most say that the reason it is forbidden is because it is not zeh v'zeh gorem since the fuel is the primary contributor to the baking. Some say that the reason that in fact it is considered zeh v'zeh gorem and nonetheless, it is forbidden because the loss of food is a minimal loss and initially we are strict on zeh vzeh gorem unless there's a large loss.[19]

Changing the Product

  1. Something affected by a forbidden factor is only forbidden when it changes the product. Food that was placed in a forbidden utensil does not become forbidden.[20]
  2. Food cut with a knife that was forbidden from benefit according to some becomes forbidden from benefit, while others hold it does not since a cut isn't considered a significant change.[21]

Coals of Prohibited Items

  1. Avoda zara is forbidden even after it is burnt and becomes coals.[22]
  2. Bread cooked over avoda zara fuel which was only coals and not a blazing fire is a dispute whether it is permitted.[23]
  3. The coals of Orlah, Kilayim, or other prohibitions are forbidden on a rabbinic level.[24] If one baked bread over coals of something forbidden the bread is permitted.[25]

Examples of Zeh V'zeh Gorem

  1. An animal born to one parent which is forbidden and another which is permitted is an example of zeh v'zeh gorem.[26]
  2. Two trees which are grafted one onto the other and one is orlah and the other isn't is an example of zeh v'zeh gorem.[27]
  3. A forbidden from benefit seed or fruit planted in the ground is a dispute if that is an example of zeh v'zeh gorem since the ground contributes to the growth but works differently than the seed.[28]
  4. Two pieces of sour dough, one which is forbidden and one which is permitted, used to ferment a dough is considered zeh v'zeh gorem if they are nullified in it of themselves.[29]

Zeh Yachol Vzeh Yachol

  1. If each factor were independently capable of causing the intended product, the product is forbidden and not considered zeh v'zeh gorem.[30]


  1. Pesachim 26b, Avoda Zara 49a, Rif Avoda Zara 21b, Rosh Avoda Zara 3:8, Ramban Avoda Zara 49b s.v. vkayma, Ritva Avoda Zara 49a s.v. Mishna Natal, Rambam Machalot Asurot 16:22, Shulchan Aruch Y.D. 142:4
  2. Ran Avoda Zara 21a-b clearly explains that zeh vzeh gorem is based on nullification. Meiri 26b s.v. kol implies this as well. Also, Kesef Mishna Nedarim 5:15 and Avnei Meluyim subscribe to this contention. Nachalat Baruch 10 shows that this approach isn't necessarily accepted by Tosfot and other rishonim. Shaarei Yosher 3:26:674-7 explains that the reason zeh vzeh gorem is permitted is because we view the prohibited factor as contributing nothing since it wasn't able to create the intended result on its own.
  3. Rambam Machalot Asurot 16:24, Shulchan Aruch Y.D. 142:7. Kesef Mishna's first explanation of the Rambam is that the food was cooked originally with forbidden fuel and then with permitted fuel and is forbidden. Meiri 26b s.v. lifi quoting some mefarshim, Michtam 26a s.v. ulinyan, Shach YD 142:13, Taz 142:9 all accept this explanation. The Kesef Mishna's second explanation is the pot was finished with forbidden fuel and then the food was cooked with permitted fuel and is forbidden. He himself prefers the first explanation. Radvaz Machalot Asurot 16:24 agrees with the second explanation.
  4. Maharam Chalavah Pesachim 27b s.v. lmaan clearly writes that the bread produced with forbidden fuel is biblically forbidden. However, the Tosfot Pesachim 75a citing Ri and Ran Avoda Zara 22b s.v. vgarsinan hold that that they're only rabbinic. Avnei Meluyim 6 cites this Ran and applies it to all things which were produced by a forbidden factor. Gra YD 331:41 writes that it is a dispute whether getting the benefit from burning something that is forbidden in benefit is biblical; the Rash Trumot 11:9 holds it is rabbinic and Tosfot Pesachim 9a s.v. kdi holds it is biblical.
  5. Rashi Avoda Zara 66b s.v. shein, Tosfot Pesachim 26b s.v. chadash, Tosfot Chachmei Angliya 26b s.v. yesh, Rabbi Akiva Eiger on Nedarim 6:7
  6. Pesachim 27a, Rav Elchanan in Pesachim n. 119
  7. Tosfot Avoda Zara 43b s.v. amru imply that zeh vzeh gorem is relevant to chametz and permitted according to those who usually permit zeh vzeh gorem. Avnei Meluyim 7 accepts this proof and explains that since chametz when used as a gorem is only rabbinic, rabbinic chametz can be nullified. Also, Gra OC 445:9 permits and rejects the Magen Avraham's proof from Pesachim 27b because hekdesh is uniquely strict and it isn't similar to other prohibitions which can't be nullified. Biur Halacha 445:2 s.v. asurim notes that the Magen Avraham's view on the matter is largely rejected. Maharam Chalavah Pesachim 29a s.v. vlinyan also permits zeh vzeh gorem for chametz.
  8. Magen Avraham 445:5, Avnei Meluyim 6, and Maharsham 1:131. Magen Avraham is based on the Ramah cited by Tur YD 142 that zeh vzeh gorem is forbidden for avoda zara since it isn't nullified and so too chametz. Avnei Meluyim agrees with the Magen Avraham with respect to chametz but disagrees with his proof from avoda zara and sides with the Shach who explains that even the Ramah permitted zeh vzeh gorem with respect to avoda zara since nullification is somewhat relevant to avoda zara.
  9. Yeshuot Yakov 448:9 originally proposes that milk from a cow that was fed chametz on pesach should be forbidden. His reasonings in his conclusion are unclear. Encyclopedia Talmudit (Zeh Vzeh Gorem fnt. 110-111) cites Torat Chesed 21, Peleti 60, Bet Efraim 35, Nishmat Adam 9, and Chelkat Yoav 20 as ruling leniently on this question.
  10. Gemara Avoda Zara 48b, Ramban Avoda Zara 49b s.v. vkayma, Ritva Avoda Zara 49a s.v. Mishna Natal, Shach YD 142:10, Avnei Meluyim 6
  11. Taz 142:4, Magen Avraham 445:5. The Ramah cited by Tur 142:4 seems to forbid it as the Tur proves that the Rosh agrees as he quotes the Mishna that a new oven finished with avoda zara fuel must be broken. This is the understanding of the Bet Yosef, though he personally disagrees with the Ramah considering the proof from Avoda Zara 48b that zeh v'zeh gorem applis to avoda zara. However, the Shach 142:10 carefully answers all the implications of the Tur and explains that the Ramah was only saying that the bread cooked over avoda zara fuel is forbidden and the proof in the Tur was from the Mishna that the bread is forbidden and not the oven. Taz defends the Ramah as understood by the Bet Yosef and accepts that approach. He answers that the Gemara Avoda Zara 48b only permitted zeh v'zeh gorem for fertilizer where it is merely an improvement of the ground but not a factor that creates the production unlike the other explains of zeh v'zeh gorem. Magen Avraham 445:5 says that we're strict on zeh v'zeh gorem by avoda zara since it isn't nullified as the Shach and Taz hold. Avnei Meluyim corrects the Magen Avraham that he meant that he is following the Taz and not Shach.
  12. Maharsha Pesachim 27b s.v. lrabbanan rejects the interpretation of the Maharshal that the gemara means zeh v'zeh gorem is forbidden by hekdesh because it isn't nullified on the basis of the question that avoda zara isn't nullified and yet is permitted with zeh v'zeh gorem.
  13. Maharshal Pesachim 27b s.v. lrabbanan translates the gemara to be discussing zeh v'zeh gorem of hekdesh and it concludes that it is forbidden. Avnei Meluyim 6 concurs with this interpretation and shows that it lines up with the Shach 142:10 and Magen Avraham 445:5.
  14. Ran Avoda Zara 21a-b clearly explains that zeh vzeh gorem is based on nullification. Also, Kesef Mishna Nedarim 5:15 says that for dvar sheyesh lo matirin we would not apply zeh vzeh gorem muter. Avnei Meluyim 6 elaborates on the approach of the Kesef Mishna.
  15. Chikrei Lev YD 2:2-4 proves this from Temurah 28b that the offspring of a invalid korban is invalid as a korban but it is only one parent that is invalid zeh vzeh gorem is relevant, even though animals are significant. He distinguishes this from the case of dvar sheyesh lo matirin that zeh vzeh gorem isn’t applicable.
  16. Tosfot Pesachim 26b s.v. ben, Baal Hameor Pesachim 6b s.v. vaf, Rosh Pesachim 2:2 s.v. vlo, Ran Pesachim 7a s.v. ha, Ritva Avoda Zara 49a s.v. Mishna Natal, and Tur 142:4. For other approaches see Raavad on Rif, Meiri 26b, and Michtam. Avnei Meluyim asks why a large loss permits zeh v'zeh gorem initially if the Ran compares zeh v'zeh gorem to nullification and it is forbidden to nullify something forbidden initially even to avoid a loss. He answers that according to the Rashba who says that ein mevatlin isur lechatchila does not apply when it isn't possible to come to violate the actual prohibition, such as by cooking in a pot with a minimal amount of absorbed tastes which are always nullified. However, the Ran disagrees with the Rashba's idea. Instead he suggests that perhaps there is no prohibition of ein mevatlin isur lechatchila here since it doesn't apply to rabbinic prohibitions and items produced by a forbidden factor are only rabbinic. See there where he isn't certain about this answer for the Ran. See further, the Ran both on the Rif Pesachim 7a and Chiddushin Pesachim 26b does assume that zeh v'zeh gorem is initially forbidden but permitted to avoid a loss.
  17. Shach YD 60:5. See Erech Hashulchan 99:8 who associates this to the question of buying something from a non-Jew which has nullification.
  18. Tosfot, Tosfot Shantz, Tosfot Rosh, Ran, Rosh, Ritva
    • Is the permitted oven considered a contributing factor if there's forbidden fuel? Maharam Chalavah Pesachim 26b s.v. lo asks why bread produced in a permitted oven with forbidden fuel is forbidden according to Rebbe if the gemara supposes that Rebbe might hold zeh v'zeh gorem is permitted. He answers that zeh v'zeh gorem is only permitted after the fact and eating the bread would be relying on zeh v'zeh gorem initially. Similarly, Maharsha 26b s.v. iymur and Maharshal 27b s.v. lrabbanan understand that the oven is a contributing permitted factor even when cooking with forbidden fuel, while the Karnei Reem 26b:1 and 27b:3 notes this and disputes their view on the basis of the Peni Yehoshua. This parallels the Kesef Mishna Machalot Asurot 16:24's first question on his first approach where he accepts this premise, while the Taz 142:9 who rejects this questions accepts the view of the Peni Yehoshua. [Michtam 26b s.v. lo kasha writes that the oven is a contributing permitted factor when cooking with forbidden fuel and fnt. 23 to Maharam Chalavah contends that the Michtam agrees with the Maharam Chalavah, however, according to the Peni Yehoshua's reading of Tosfot that the oven is a contributing factor in comparison with forbidden fuel that has died down and became a coal or disembodied heat, the Michtam isn't such a clear proof.]
    • However, the Peni Yehoshua 26b s.v. btosfot s.v. ben argues with the Maharsha and see the oven as a contributing factor only if it is forbidden and the fuel is permitted, however, when the oven is permitted and the fuel is forbidden the primary contributing factor is the fuel and it is forbidden. This is evident in the Ran Avoda Zara 21b s.v. Mishna Natal who explains that cooking bread over forbidden fuel is worse than typical zeh v'zeh gorem since the result of the forbidden fuel is evident in the product. Ritva Avoda Zara 49a s.v. Mishna Natal and Tur 142:4 agree. Meiri Pesachim 26b s.v. kol explicitly endorses this approach that the permitted oven is a competitive contributive factor when discussing forbidden coals or heat but when discussing a blazing fire from forbidden fuel the fuel is primary and the oven is not a contributing factor. Tzlach 27a s.v. vim and Dvar Shmuel agree with the Peni Yehoshua.
    • Summary: Maharam Chalavah, Michtam, Maharsha, Maharshal, and Kesef Mishna think that the permitted oven is a contributing factor and zeh v'zeh gorem is relevant, while the Ran, Ritva, Meiri, Peni Yehoshua, Karnei Reem, Taz Tzlach, and Dvar Shmuel opine that the fuel is the primary contributor and zeh v'zeh gorem is irrelevant.
  19. Meiri Pesachim 26b s.v. kaarot according to all opinions
  20. Meiri Pesachim 26b s.v. kaarot quotes some who permit it and he forbids it. Rabbenu Dovid Pesachim 26b s.v vyesh permits.
  21. Gemara Pesachim 27b
  22. Shulchan Aruch 142:6, Bet Yosef 142:4, and Rama 142:4 permit, while Shach 142:10, Taz 142:5, and Gra 142:7 forbid. The Bet Yosef acknowledges that although the coals of avoda zara are indeed forbidden they do not make the bread forbidden since it isn't a blazing fire and the coals are only forbidden initially. He infers this from the Tur 142:4. However, the Shach 142:10 argues that it is forbidden since the coals of avoda zara are forbidden and would make the food produced over it forbidden. He quotes a Tosefta Orlah 1 which corroborates this point. Shach infers this from the Rambam Avoda Zara as well. Shaar Hamelech cited by Pitchei Teshuva 142:2 addresses the questions of the Shach for the Bet Yosef and distinguishes between coals that are a result of avoda zara that was burnt and a coal which was used for avoda zara when it was already a coal.
  23. Tosfot Pesachim 5a s.v. kol
  24. Gemara Pesachim 26b. Tosfot Pesachim 26b s.v. bishla distinguishes between coals and ashes.
  25. Temurah 28b
  26. Avoda Zara 49a
  27. Rashi's first explanation posits that it is an example, while his second does not. Tosfot disputes Rashi's first explanation because the ground's contribution is fundamentally differently than that of the seed.
  28. Pesachim 27a
  29. Tosfot Avoda Zara 68b and Mordechai unlike Tosfot Pesachim 27a. Tosfot 27a s.v. ad notes that Rabbi Shimon permits zeh yachol and zeh yachol and that corresponds with the opinion that zeh vzeh gorem when it is zeh eino yachol vzeh eino yachol. However, the prohibited case is where there’s not enough of the permitted ingredient and enough of the prohibited one. His logic is that we never found a third opinion in this matter, so Rabbi Shimon must permit because of zeh vzeh gorem. However, the Tosfot A”Z 68b s.v. ela says that Rabbi Shimon is matir zeh yachol vzeh yachol, while the others who usually hold zeh vzeh gorem is only muter if it isn’t zeh yachol. It is more chamur when it is zeh yachol zeh yachol. Shach YD 87:36 says that this is the ruling of the Mordechai and Rama. Taz 87:13 and Pri Chadash 87:31 agree. Pri Chadash proves the Shach's point from the Rambam Machalot Asurot 16:16, who usually holds eh vzeh gorem muter regarding ovens and still says zeh yachol zeh yachol is forbidden. Peleti 87:21 thinks Tosfot a”z isn’t arguing on Tosfot pesachim since they’re only lenient since it is noten taam lifgam. Tosfot Rash and Tosfot Rosh imply otherwise. Imrei Binah Basar Bchalav 5 s.v. vheneh notes another way to dispute the Peleti is that it isn’t noten taam lifgam since it is reuy lchameya isa acheret.
Category Topics
Bishul Akum - Checking for Bugs - Gelatin - Kosher Food without Kosher Supervision - Kosher Food Packaging for Deliveries - Kosher Food Left with a Non-Jew - Koshering a Kitchen - Kashering for Pesach - Kosher in the Workplace - Medications - Pat Palter - Selling Non-Kosher Foods - Serving Guests - Sharp Foods - Shechitah (Kosher Slaughter) - Tevilat Keilim - Tzaar Baalei Chayim - Yashan
Meat and Milk
Dairy Bread - Eating Dairy and Meat at the Same Table - Kosher Cheese - Kosher Milk (Chalav Yisrael) - Milk and Meat in the Kitchen - Non-Dairy Milk - Waiting between Meat and Milk
Principles of Kashrut
Items That Cannot Be Nullified - Transferring Taste - Nullification - Zeh Vzeh Gorem - Trusting Others for Kashrut
Shechitah_(Kosher_Slaughter) - Who_Can_Be_a_Shochet - The_Shechitah_Knife - Modern_Day_Industrial_Shechitah - Glatt Kosher Meat - Kashering Meat