The Gemara answers: One can say that Rabbi Meir says that priests are suspect with regard to causing blemishes only to the extent that there is a concern that they might have caused a blemish. But did he say this ruling to establish them as those who definitely cause blemishes? Certainly not.

§ A dilemma was raised before the Sages: With regard to testimony based on hearsay, where one repeats the testimony of another witness, what is the halakha in a case of such testimony about a blemished firstborn animal? Rav Asi deems prohibited the slaughter of the animal based on such testimony, and Rav Ashi deems it permitted. Rav Asi said to Rav Ashi: But isn’t it taught in a baraita in the school of Menashe that hearsay testimony is valid only for the testimony of a woman, where one testifies that her husband is dead? This indicates that such testimony is not accepted in all other instances.

Rav Ashi responded: Emend the baraita and teach it like this: Testimony based on hearsay is valid only for that testimony for which the testimony of a woman is valid. According to Rav Ashi, the baraita is teaching that any case where the testimony of a woman is valid, hearsay testimony is valid as well, and this includes testimony concerning a blemished firstborn animal.

The Gemara relates that Rav Yeimar deemed fit testimony based on hearsay with regard to a blemished firstborn animal. Mareimar condescendingly called him: Yeimar who permits firstborn animals. The Gemara concludes: And the halakha is that testimony based on hearsay is valid in the case of a firstborn animal.

§ The Gemara discusses a related matter. Rabbi Ile’a says: In a case where a blemished animal was not established as being a firstborn, and one priest came to an expert and said that it is a firstborn animal and yet its blemish is with it, i.e., it was unintentionally blemished, he is deemed credible, and the expert may deem the animal fit for slaughter based on the priest’s testimony.

The Gemara asks: What is Rabbi Ile’a teaching us? Is he teaching us the principle that the mouth that prohibited it is the mouth that permitted it, i.e., when the only source that an item was prohibited is the statement of one who says that it is now permitted, his claim is accepted? But we learn this in a mishna (Ketubot 22a): With regard to a woman who said: I was a married woman and now I am a divorcée, she is deemed credible and permitted to remarry, as the mouth that prohibited her by establishing that she was married is the mouth that permitted her by establishing that she was divorced.

The Gemara answers: Rabbi Ile’a’s statement is necessary, lest you say it is only there, in the case of the mishna, that the woman’s testimony is accepted, as, if she wants to remarry illegally, she does not need to say anything at all about previously being married. But here, with regard to the firstborn animal, it is different, as, if the priest wishes to eat the meat of the animal, it not sufficient for him not to bring the animal to an expert, i.e., he has no recourse other than to say that it is a firstborn animal which has a blemish requiring examination, as he cannot determine on his own whether this blemish permanently disqualifies the firstborn animal from sacrifice, and he would not eat sacrificial meat outside the Temple courtyard, which is punishable by karet.

Since the priest must admit that this is a firstborn animal, I might say that this is not a case of: The mouth that prohibited it is the mouth that permitted it, and therefore the priest is not deemed credible. To dispel this possibility, Rabbi Ile’a teaches us that he is deemed credible, because if it due to that reason, that the priest is suspected of causing the blemish, he would have caused a blemish that is obvious to all. In such a case, he would violate a mere prohibition, not one that is punishable by karet, since he would not be eating sacrificial meat outside the Temple courtyard, as the animal is blemished.

Mar bar Rav Ashi objects to this: What is different between this case and that incident involving a certain man who rented a donkey to another? The owner said to the renter: Look, do not go on the path of Nehar Pekod, where there is water and the donkey is likely to drown. Instead, go on the path of Neresh, where there is no water. The renter went on the path of Nehar Pekod and the donkey died. When he came back, he said: Yes, I went on the path of Nehar Pekod, but there was no water there, and therefore the donkey’s death was caused by other factors.

And Rava said: The renter’s claim is accepted, due to the reasoning of: Why would he lie and state this claim? In other words, if this man wanted to lie, he could have told the donkey’s owner: I went on the path of Neresh, as the owner instructed. And Abaye said to Rava: We do not say the principle of: Why would he lie, in a place where there are witnesses. Since witnesses can be summoned to establish conclusively whether there was water along the path of Nehar Pekod, the reasoning that the renter could have stated a different claim is not employed. Similarly, the priest’s contention that the blemish occurred inadvertently should not be deemed credible, as it is known that priests are suspected of causing blemishes.

The Gemara rejects this suggestion: How can these cases be compared? There, with regard to the path of Nehar Pekod, there is certainly water there, but here, the possibility that the priest caused a blemish in the firstborn animal is only a concern, and in a place of mere concern we do say the reasoning of: Why would he lie? The Gemara relates that Ravina was sitting and saying this halakha of Rabbi Ile’a anonymously. Rava Zuti said to Ravina: We learned this halakha in the name of Rabbi Ile’a.

§ The Gemara relates: Rabbi Tzadok, an erudite priest, had a firstborn animal. He placed barley in wicker baskets for it, and while it was eating, its lip split, rendering the animal blemished. Rabbi Tzadok came before Rabbi Yehoshua, to ask whether or not he is suspected of intentionally causing a blemish in his firstborn animal offering. Rabbi Tzadok said to him: Didn’t we differentiate between a priest who is a ḥaver, i.e., learned, and a priest who is an ignoramus, with regard to their credibility about blemishes found on a firstborn animal? Rabbi Yehoshua said to him: Yes, we did. Since you are a learned priest, you are deemed credible to testify that this blemish was caused inadvertently.

Rabbi Tzadok then came before Rabban Gamliel, the Nasi and head of the academy of Yavne at the time. Rabbi Tzadok said to him: Didn’t we differentiate between a priest who is a ḥaver and a priest who is an ignoramus with regard to credibility about blemishes found on a firstborn animal? Rabban Gamliel said to him: No, we did not. Rabbi Tzadok said to him: But Rabbi Yehoshua said to me that yes, we did differentiate in this manner. Rabban Gamliel said to Rabbi Tzadok: Wait until the masters of the shields [ba’alei terisin], a reference to the Torah scholars who battle in the war of Torah, enter the study hall, at which point we will discuss this issue.

When the Torah scholars entered the study hall, the questioner stood before everyone present and asked: With regard to blemishes found on a firstborn animal, didn’t we differentiate between a priest who is a ḥaver and a priest who is an ignoramus? Rabbi Yehoshua said to him: No, we did not. Rabban Gamliel said to him: But they said to me in your name that yes, we did differentiate.

Rabban Gamliel continued: Yehoshua, stand on your feet and they will testify against you that you did, in fact, say that we differentiated in such a case. Rabbi Yehoshua stood on his feet and said: How should I act in this situation? If I were alive and Rabbi Tzadok were dead, the living can contradict the dead, and I could deny issuing that ruling. Now that I am alive and he is alive, how can the living contradict the living? I have no choice but to admit that I said it.

In the meantime, Rabban Gamliel was standing and lecturing, and Rabbi Yehoshua all the while was standing on his feet, as Rabban Gamliel did not instruct him to sit. He remained standing in deference to the Nasi. This continued for some time, until it aroused great resentment against Rabban Gamliel, and all of the people assembled began murmuring and said to Ḥutzpit the disseminator: Stop conveying Rabban Gamliel’s lecture, and he stopped.

MISHNA: A priest is deemed credible to say: I showed this firstborn animal to an expert and he ruled that it is blemished.

GEMARA: Rav Yehuda says that Rav says: A priest is deemed credible to say: An Israelite gave me this firstborn animal with its blemish already inflicted upon it. What is the reason? With regard to any matter that is likely to be revealed, people do not lie about it. Since the Israelite can be questioned with regard to the veracity of the priest’s claim, it is assumed that the priest will not risk lying. Rav Ashi said: We learn a similar principle in the mishna as well: A priest is deemed credible to say: I showed this firstborn animal to an expert and he ruled that it is blemished. What is the reason the priest’s claim is deemed credible? Is it not because we say that with regard to any matter that is likely to be revealed, people do not lie about it?

The Gemara rejects the claim that the mishna’s ruling is based on the principle that people do not lie about a matter that is likely to be revealed: Perhaps there, in the case of the mishna, the reason the priest’s claim is accepted is that he would not eat sacrificial meat outside the Temple courtyard. If an expert had not permitted the meat, the priest would not eat it. But here, in Rav’s case, where the priest claims an Israelite gave him an already blemished animal, since priests are suspected of causing blemishes and claiming that it was inadvertent, they are also suspected of causing a blemish and claiming it was given to them in that state by an Israelite.

Rav Sheizevi raises an objection to Rav’s ruling from a mishna (Demai 4:5): In the case of one who says to someone who is not trusted with regard to tithe: Purchase produce for me from someone who is trusted with regard to tithes, i.e., one who does not purchase produce from an ignoramus, who generally does not separate tithes; or if he says: Purchase produce for me from someone who tithes, i.e., even from one who purchases produce from an ignoramus but is careful to set aside tithes upon purchasing the produce, the agent is not deemed credible to claim that he fulfilled the condition of the one who appointed him. According to Rav, why isn’t the agent deemed credible? Say the principle that with regard to any matter that is likely to be revealed, people do not lie about it.

The Gemara answers: It is different there,