The Shechitah Knife

From Halachipedia

What Can Be Used for Shechitah

  1. Technically, anything that is detached from the ground and sharp can be used for kosher slaughter, as long as it's free of imperfections. A reed membrane would be good if it doesn't have any splinters that would come out. Practically, however, this is exclusively done with a knife.[1]
  2. One shouldn't use a scythe or even a double edged knife if one side of it is a scythe. Bediavad if he did it and knows he used the kosher side, it's ok, and if he smoothened out the scythe side then he can use it lechatechilah.[2]

Detached From Its Source

  1. Anything sharp attached to the ground or a body may not be used for shechitah until it is detached.[3]
  2. If it was detached and then reattached, one still should not use it regardless of whether he plans to leave it there (which would render the meat prohibited due to the Gemara's uncertainty) or not (which would be invalid on a rabbinic level). If one's intention is unformulated, we can determine based on context.[4]
  3. An animal's jaw with sharp teeth may not be used, as the gaps between teeth are the same as nicks in a knife, but a singly tooth attached to a jaw is fine. Even a single nail on a severed foot would be ok. Some argue that if it's still attached to a whole limb, such as a whole jaw or whole animal foot, that would be considered "attached" to its source of growth.[5]

Pegimot

  1. A knife with a pegima (nick) may not be used. Bediavad, if one used it and claims he didn't use that part of the blade, the meat is kosher, but if he didn't realize it was there until afterwards, he has no claim.[6]
  2. Ideally even if one covers the pegimah, he might accidentally use the part with the pegimah.[7]
  3. If the blade has two edges, one must make sure both are free of pegimot.[8]
  4. On Yom Tov or in pressing circumstances, one can cover the pegima and shecht carefully, avoiding the pegimah, as long as there are two neck widths of length left of the knife from the pegimah in either direction and one shechts in a sawing motion. Some say the length is measured from the end of the cloth and not the pegimah. All this applies for two pegimot with enough blade length in between, as well.[9]

Glowing Hot Knife

  1. A knife that is heated till it glows (incandescent) may not be used, as the heat from the sides of the blade burns the simanim before the blade finishes severing them, resulting in a piercing instead of a shechitah. The meat would be prohibited on a Torah level. Some are lenient bediavad if the shochet was aware and maneuvered the knife in a way that avoids the sides touching the simanim, but the halacha follows the strict view. Some say the minimum temperature of the metal is Yad Soledet Bo.[10]

Non-Kosher Knives

See [Koshering a Kitchen] for more details.

  1. Due to the temperature of the animal neck and potentially also to the pressure of the knife, one may not use a non-Jew's knife before kashering it or sanding down a layer from both sides of the knife. Hagala is sufficient unless there are holes in the blade, which would then require libun.[11]
  2. If the animal was shechted with non-kosher knife that was not used for non-kosher food in the past twenty-four hours (eino ben yomo); although, the knife should have ideally been kashered, the meat is kosher. The same is true if one is unsure if it was used in the past twenty-four hours. If there is any visible non-kosher substance on the blade, as knives are often not perfectly clean, then the rules of an actual ben yomo must be followed as below. Even if one thinks it was clean, there's room to be strict as below, unless one made sure to do a thorough job or it is a pressing situation.[12]
  3. If it was definitely used for non-kosher in the past twenty-four hours (ben yomo) but not kashered, a layer must be sliced off (kelipah) from the neck, due to the potential for non-kosher substances on the blade to rub off and be absorbed in the neck and generally these things are not absorbed deeper than a kelipah. Some argue that even if the knife was cleaned of surface substances properly with neitzah, there's still a concern for absorption of flavor facilitated by the heat of the animal neck and the pressure of the blade as well as non-kosher substances that are hard to see but still present on the blade. Without kelipah, cooking the meat would require measuring if the kelipah is less than one sixtieth of the rest of the meat and then kelipah.[13]

Knives Used for Idolatry

  1. One may not benefit from tools used to worship an idol, therefore, the knife used to slaughter animals for idolatrous sacrifices is prohibited from benefit. That said, killing a healthy animal is arguably more detrimental than it is beneficial, as the animal is no longer alive to grow or work. A dead animal is only good for its meat and entails a necessary loss. Similar arguments could be made for birds. As such, shechting a healthy animal or bird with a knife used for idolatrous activities is permissible, because causing a loss is not considered benefit. However, a sick animal may not be shechted with that knife, as that would be considered an improvement. Some argue the same is true for a very violent or high maintenance animal that comes at a loss to its owner or if the price of meat is higher than the price of the animal it comes from.[14]
  2. If the knife was used to cut wood which was then used for idolatry, then it's permissible. It's only considered a knife of Meshamshei Avodah Zarah when the idol is finished with the knife or sacrifices are slaughtered with it.[15]
  3. A sick animal slaughtered with a knife of Meshamshei Avodah Zarah is entirely prohibited from benefit until one throws away enough meat the value of which is equal to the cost of shechting with it. If there aren't any more knives avaialble, then the cost of shechting must go up.[16]

Crafting a Shechitah Knife

Modern day shechitah knives are commonly rectangularly shaped to facilitate shechitah without issues of chaladah and derasa and made with easy to sharpen steel that maintains its edge to minimize pegimot.

 
Chalef with Blue Bone Handle, image courtesy of Laevi Sussman, JewishKnives.com
  1. One should use a knife that ends in a right angle, not a sharp point, in order to avoid chaladah. In pressing circumstances, can can cover the tip with something light and then shecht (a hard tip cover could lead to derasa).[17]
  2. Some say the top of the knife should also be void of pegimot,[18] in case one ends up cutting with the top, while others note how the rectangular knives we use today avoid this issue.[19]
  3. The ideal shechitah knife is twice as long as the neck of the target category;[20] therefore, bird (ofos) knives are usually about five inches long, sheep (dakos) knives are usually nine inches long, and cattle (gasos) knives are usually about sixteen inches long.[21]
  4. The instrument used to shecht should preferably be as smooth as possible on both sides. Therefore, although engravings in the blade far from the edge do not render the shechitah invalid, but one should ideally use a knife free of any engravings. Anything sticking out of the side would be a problem even bediavad despite being far from the edge.[22]
 
Stainless Steel Chalefim in Select Sizes, image courtesy of Laevi Sussman, JewishKnives.com

Sharpening a Shechitah Knife

Sharpening a knife is done by grinding the edge against coarse and then fine whetstones, back and forth, one side and then the other, until the knife is sharp and smooth.

Checking a Shechitah Knife

Guides

Purchasing a Knife

Sources

  1. ↑ Simla Chadasha 6:1
  2. ↑ Simla Chadasha 6:2
  3. ↑ Simla Chadasha 6:5
  4. ↑ Simla Chadasha 6:5
  5. ↑ Simla Chadasha 6:6
  6. ↑ Simla Chadasha 6:3
  7. ↑ Simla Chadasha 6:3
  8. ↑ Simla Chadasha 6:3
  9. ↑ Simla Chadasha 6:3
  10. ↑ Simla Chadasha 9:1
  11. ↑ Simla Chadasha 10:4
  12. ↑ Simla Chadasha 10:7
  13. ↑ Simla Chadasha 10:5-7
  14. ↑ Simla Chadasha 10:1
  15. ↑ Simla Chadasha 10:2
  16. ↑ Simla Chadasha 10:3
  17. ↑ Simla Chadasha 6:4
  18. ↑ Simla Chadasha 6:4
  19. ↑ Mateh Asher 6:5
  20. ↑ See Simla Chadasha 8:2 and [The Shechitah Process] for more details.
  21. ↑ See IBC Experiential Halacha: Chicken Shechita
  22. ↑ Simla Chadasha 9:2
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
Shechitah_(Kosher_Slaughter) - Who_Can_Be_a_Shochet - The_Shechitah_Knife - Modern_Day_Industrial_Shechitah - Glatt Kosher Meat - Kashering Meat
Retrieved from "http://localhost:80/index.php?title=The_Shechitah_Knife&oldid=32083"