Bechoros Daf 16 בכורות דַף 16

Rav Nachman said that the תמורה of a redeemed, blemished korban is left to die, because there is no alternative:ליקרביה  – should we sacrifice it on the מזבח? מכח קדושה דחויה קאתיא – But [its kedushah] comes from rejected sanctity (i.e., a redeemed korban). ליפרקה – Should we redeem it? לא אלימא למיתפס פדיונה – [Its kedushah] is not strong enough to take hold of its redemption money. Rav Amram objects that the owner should eat it after it develops a מום, like the halachah for the temurah of a בכור and מעשר!? Abaye explains: זה שם אמו עליו – this one bears the name of its “mother” (i.e., the original bechor or maaser, its source of kedushah), וזה שם אמו עליו – and this one bears the name of its mother (i.e., the redeemed korban). Thus, תמורת בכור ומעשר מיקריא – [this temurah] is called “temurah of bechor and maaser”; just as bechor and maaser are eaten by their owner after developing a מום (without פדיון), the same applies to their temurah. Rav Nachman’s case is called the temurah of kodashim; just like kodashim, it cannot be eaten without פדיון. Since פדיון here is impossible, it must be left to die.

Rav Nachman’s ruling above is supported by a Baraisa, which derives that the temurah of פסולי המוקדשין is left to die from the passuk "ממעלי הגרה...טמא" – from those which bring up their cud…is tamei [to you], teaching that there is an animal with kosher signs which is prohibited. The Gemara objects that this passuk is needed to teach that חמש חטאות מתות – five חטאות are left to die (e.g., a חטאת whose owner died)!? It answers that those are darshened from the next phrase,"ממפריסי הפרסה...טמא"  – from those which have split hooves. The Gemara then asks that the law of the חמש חטאות המתות is הילכתא גמירי לה – learned through a הלכה [למשה מסיני], and the derashah should be unnecessary!? It answers that the הלכתא is necessary to teach that the חמש חטאות are left to die, and not to merely graze until developing a מום. The passuk is necessary to teach that if one does eat from one of the חמש חטאות, he violates not just a transgression, but a לאו. Alternatively, the passuk is needed to compare the חמש חטאות with the temurah of a redeemed korban, teaching that it is also left to die.

The next Mishnah states: המקבל צאן ברזל מן העובד כוכבים – if one accepts animals as a צאן ברזל arrangement with an idolator, i.e., the Jew accepts complete responsibility for any losses, and they divide the profits, ולדותיהן פטורין – their offspring are exempt (from their own offspring having bechor status), ולדי ולדותיהן חייבין – but their offspring’s offspring are subject to bechor status (regarding their own offspring, the fourth generation). This ruling implies that כיון דלא נקט מרא זוזי – as long as the owner has not received money in exchange for his animals, ברשותא דמרא קיימא – they stand in his possession. The Gemara asks that this contradicts another Mishnah, which prohibits accepting property as a צאן ברזל arrangement from another Jew, because the owner’s profits are רבית. This proves that the capital of צאן ברזל is ברשותא דמקבל קיימא – in the recipient’s possession, like a loan (and therefore subject to ribbis)!? Rava ultimately answers that in our Mishnah, since if the Jew does not pay the עכו"ם at the end of the term, the עכו"ם might seize the offspring, it is considered יד עובד כוכבים באמצע – “an idolator’s hand in the midst,” which is exempt from bechor without actual ownership.