Chullin Daf 18 צולין דַף 18

Rav Huna said: האי טבחא דלא סר סכינא קמי חכם– if a שוחט did not show his knife to a sage to be examined, משמתינן ליה – we place a ban upon him for his brazen dishonor to the חכם. Rava said: מעברינן ליה – we remove him from being allowed to sell meat, ומכרזינן אבשריה דטרפה היא – and announce that his meat is not kosher. These opinions do not argue; Rav Huna’s ruling is בשנמצאת סכינו יפה – where his knife was found to be fine (without nicks), and Rava’s stricter penalty applies where the knife was found faulty. Ravina says that where the knife was found faulty, his meat is smeared with excrement, so it cannot even be sold to an idolator. There was a שוחט who did not show his knife to Rava bar Chinana, who placed a ban on him, removed him from his post, and declared his meat non-kosher. Later, he asked Mar Zutra and Rav Ashi to look into the matter, since young children depended on the שוחט. Rav Ashi found the knife to be flawless, and reinstated the שוחט, and explained to Mar Zutra that he was fulfilling Rav bar Chinana’s directive.

The Mishnah discusses one who begins shechitah within the prescribed area for shechitah and then inclines the knife, finishing above that area (called הגרמה). It states: השוחט מתוך הטבעת – if one shechts within the ring (i.e., the "טבעת גדולה" – the great ring, the highest ring of cartilage in the trachea), ושייר בה מלא החוט על פני כולה – and left a hairbreadth of it along its entire circumference, the Tanna Kamma rules the shechitah valid, since he did not deviate above this ring for any part of the shechitah. Rebbe Yose bar Rebbe Yehudah says that מלא חוט על פני רובה – a hairbreadth (of the טבעת) along most of its circumference is sufficient, even if the shechitah ended above the טבעת. He holds that cutting most of the קנה in the prescribed area is sufficient. Rav and Shmuel pasken like this second opinion. However, they rule that shechitah is only valid in טבעת הגדולה – the great ring, הואיל ומקפת את כל הקנה – since it surrounds the entire trachea, but not in שאר טבעות – the other rings of the trachea (which do not completely encircle the קנה), and one must shecht between these rings. Although Rebbe Yose bar Rebbe Yehudah himself did validate shechitah in these טבעות, Rav and Shmuel did not follow this ruling.

The Gemara records the rulings of several Amoraim who validate shechitah beyond the טבעת הגדולה. They rule like Rebbe Chanina ben Antignos, who testified that מוגרמת – a slanted cut is valid, even completely past the טבעת הגדולה. Rebbe Shimon ben Lakish validated shechitah בחודא דכובעא – through the point of the “helmet” (the peak of the thyroid cartilage, which is above the קנה and slopes upward, appearing like a helmet). Rebbe Yochanan declared about this leniency: גיסא גיסא – Too much! Too much! Rav Pappi quoted Rava: פגע בחיטי טרפה – if [the שוחט] met the “wheat kernels” (kernel-shaped cartilages along the “helmet,” before it begins to slope), it is not kosher. The Gemara wonders if this means פגע ונגע בהן – he met and touched the "חיטי", i.e., cut through them, or if it means פגע ולא נגע – he met [the חיטי] but did not touch them (but cut just underneath them). Several other Amoraim ruled שייר בחיטי כשרה – if he left over some of the “kernels” (i.e., cut through them, leaving some above the cut), it is valid. The Gemara concludes: משיפוי כובע ולמטה – from the slope of the “helmet” and downwards is valid, which parallels this last opinion.