(Mishnah): If one betrothed with the following items, she is not betrothed, since one may not benefit from them...Orlah (fruits of a tree in its first 3 years), Kilai Hakerem (products grown in a vineyard in which other species were planted), Shor Haniskal (an ox that will put to death because it killed a person), Eglah Arufah (calf that is killed as an atonement after a person was found murdered between two cities), Tziporei Metzorah (bird offerings brought by a leper), hair of a Nazir, a firstborn donkey, meat cooked in milk and Chulin (non-consecrated) animal slaughtered in the Temple.

If he sold these items and betrothed with the money, she is betrothed.

(Gemara): A firstborn donkey - R. Elazar said that one may betroth with it; R. Yochanan said that one may not.

R. Imi citing R. Elazar: One can learn from a Kal Vechomer that one may use a firstborn donkey to betroth...if a bechor that cannot be redeemed and eaten (unless it receives a blemish) can be used to betroth, a first donkey that can be redeemed should certainly be able to be used to betroth!

Question: What would be a practical difference between these two opinions?

Answer: If he transgressed and redeemed it without the knowledge of the owner - R. Elazar said that it is not redeemed and R. Yochanan said that it is redeemed.

There is a Beraisa that supports R. Elazar but the end of it disproves him...

The Beraisa that supports him - "One who steals a firstborn donkey must pay back double''. (This shows that it is considered the property of the owner.)

But the end of disproves him - "...as even though now (before redemption) the owner may not benefit from it, since he could redeem it and then benefit, (he receives double if someone stole it). (This disproves R. Elazar, as R. Elazar holds that even before redemption it is considered the property of the owner, so it can be used for Kidushin.)

Our Mishnah also disproves R. Elazar, as it teaches that one may not betroth with a firstborn donkey!

Resolution for R. Elazar: Our Mishnah is betrothing with it after it was killed, so even R. Shimon agrees that she is not betrothed.

Question against resolution (Beraisa): One may not betroth with a firstborn donkey. R. Shimon permits it.

This Beraisa disproves R. Elazar in two ways - if it refers to a live firstborn donkey, the question comes from the Rabbanan's (tana kama's) opinion who rule that one may not betroth with it! If it refers to after it is killed, the question comes from R. Shimon's opinion who permits betrothing with it!

Answer (R. Chanina citing R. Yudan): The case is when it died naturally, so R. Shimon permits its use.

If a firstborn donkey was killed, one is prohibited to get benefit from it. What is the source for this? There is a Gezeirah Shavah from the case of eglah arufah using the word 'arifah' - just as an eglah arufah is buried and benefit is prohibited, so for a firstborn donkey that was killed, benefit is prohibited.

Question: According to R. Elazar who uses the Gezeirah Shavah to prohibit benefit after it was killed, it is fine;

But according to R. Yochanan there is a question - if it is already prohibited during its life, certainly after being killed it should be prohibited (so for what is the Gezeirah Shavah needed to teach)?!

Answer (R. Yaakov bar Acha citing R. Yochanan/ R. Zeira citing Rabbanan): Even according to Rabbanan (who disagree with R. Shimon) and say that it is prohibited when still alive, we need the Gezeirah Shavah, so that you will not say that since the Torah compared killing it to redeeming it - just as when he redeems it, it becomes Chulin, so when he kills it, it becomes Chulin.

Question: Do we find something that upon redeeming it becomes Chulin but it is prohibited when still alive?

Question: Untithed produce that had not had Maaser Ani separated -after it is separated everything becomes Chulin...

...but before it is separated, R. Ba bar Huna citing Rebbi said that one who eats it incurs the punishment of death.

Answer (Rabbanan of Kisarin citing R. Yirmiyah): The Chachamim (Rabbanan) can answer R. Shimon by asking - do we find something that requires redemption but one may benefit from it before redemption?

Response (R. Shimon): A human firstborn requires redemption but one may benefit from it before redemption.