Chullin 17b

חולין י״ז ע״ב

Learn Chullin 17b step by step: Aramaic beside English, every question, answer and proof colour-coded.

Open Chullin 17b in Gemara Clarity

Topic

Notches in a שחיטה knife: which notches disqualify, how and by whom the knife is checked, and the shared measure of a chip

Overview

A knife with many notches counts like a saw. With only one notch, an אוגרת notch makes the שחיטה invalid and a מסוכסכת notch leaves it valid. רבי אליעזר defines the two, and the גמרא narrows the case until מסוכסכת is fit only when the knife moved in one direction. רבא then sets out three levels of notch, and two reports of his view on מסוכסכת are reconciled by whether the knife went back and forth. רב אשי rules that a blade that is only slightly rough, like a grain bristle, is fully kosher. רב חסדא brings a פסוק for checking the knife, but the גמרא concludes that showing it to a חכם is only מדרבנן and the פסוק is just an אסמכתא. The גמרא lists ways to check a knife and disagrees over whether its three sides must be checked: רב פפא and the story with רב אשי say yes, while רב יימר says no because the cut opens wide. Finally, ריש לקיש lists three kinds of chips in holy animals, רב חסדא adds the knife, and all of them share the measure of a chip in the מזבח.

Opening lines

The steps (31)

1. StatementMany notches versus one notch
2. QuestionWhat do the two kinds of notch look like?
3. ResponseTwo sharp sides versus one sharp side
4. ChallengeWhy should one sharp side be any better?
5. ResolutionThe notch is at the tip of the knife
6. ChallengeBut the knife goes back and forth
7. ResolutionHe moved the knife in one direction only
8. Statementרבא's three levels of notch
9. ChallengeTwo opposite reports of רבא
10. ResolutionIt depends on back-and-forth
11. QuestionWhat about a knife that feels like a grain stalk?
12. ResponseSuch a knife is completely fine
13. StatementA Torah source for checking the knife
14. ChallengeIsn't checking the knife obvious?
15. ResolutionThe source is for showing the knife to a חכם
16. ChallengeShowing the knife to a חכם is only for his honor
17. ResolutionIt is rabbinic and the פסוק is only a support
18. StatementDifferent ways to check a knife
19. StatementIn סורא: test the knife on flesh
20. Statementרב פפא: three checks are needed
21. Questionרבינא asks רב אשי about a report in his name
22. Responseרב אשי: I did not say the three sides
23. ResponseAnother version: all three, but not from רבא
24. Proofרב אשי approves checking all three sides
25. Statementרב יימר: the sides don't need checking
26. ProofProof from שמואל's red-hot knife
27. ConclusionSame here: the cut opens, so the sides don't matter
28. StatementThree kinds of chips that matter
29. StatementAdding a nick in the knife
30. ResolutionWhy the knife was left out
31. StatementAll share the altar's measure