Here, in the final clause, it is referring to marrying a woman to him, and the halakha is that a family with no presumptive status requires investigation before one of them marries. There, in the penultimate clause, it is referring to the court removing a woman from him. The husband is not forced to divorce her unless it has been proven that they may not remain married.

Rav Yosef says: Anyone whose speech is Babylonian, i.e., anyone who speaks the Babylonian language with a Babylonian accent, is allowed to marry a woman without having his lineage examined. The presumption is that he is Babylonian, and the lineage of Babylonian families is unflawed. The Gemara comments: But nowadays, when there are swindlers who may speak with Babylonian accents in order to avoid scrutiny, we are concerned even about those who speak like Babylonians.

The Gemara relates: The Sage Ze’eiri, a Babylonian, was avoiding Rabbi Yoḥanan, who was from Eretz Yisrael, since the latter kept saying to him: Marry my daughter. One day, when they were walking along the way, they arrived at a large puddle of water. Ze’eiri lifted Rabbi Yoḥanan upon his shoulders and carried him over the puddle out of respect. Rabbi Yoḥanan said to him: Our Torah is fit and worthy of honor in your eyes, and yet our daughters are not fit? What is your reason for not wanting to marry my daughter?

Rabbi Yoḥanan continued: If we say a reason not to marry my daughter is from that which we learned in a mishna (69a): There were ten categories of lineage among the Jews who ascended from Babylonia: Priests, Levites, Israelites, as well as many of flawed lineage, and you are concerned about the mamzerim among those who live in Eretz Yisrael, is that to say that all of the priests, Levites, and Israelites ascended to Eretz Yisrael? Certainly, Jews of unflawed lineage remained in Babylonia. Just as there remained from these unflawed categories in Babylonia, there also remained individuals from these, the flawed categories. Therefore, marrying only Babylonians will not alleviate your concern. The Gemara comments: In fact, this statement of Rabbi Elazar escaped Rabbi Yoḥanan: Ezra did not ascend from Babylonia until he made it like fine flour, and then he ascended. Accordingly, the people who remained in Babylonia were all of unflawed lineage.

The Gemara relates another incident: Ulla arrived in Pumbedita to the house of Rav Yehuda. He observed that Rav Yitzḥak, son of Rav Yehuda, was grown up and was unmarried. Ulla said to Rav Yehuda: What is the reason that the Master does not marry a woman to his son? Rav Yehuda said to him: Do I know from where I can find a woman to marry him? I am concerned about flawed lineage. Ulla said to him: Is that to say that we know where we come from? Can we be sure that our lineage is unflawed? Perhaps we are from those about whom it is written: “They have ravished the women in Zion, the maidens in the cities of Judah” (Lamentations 5:11). Perhaps we are descended from women ravished by gentiles.

And if you would say that you are not concerned about that possibility, since you maintain that in the case of a gentile or a slave who engaged in sexual intercourse with a Jewish woman, the lineage of the offspring is unflawed, perhaps we come from those about whom it is written: “That lie upon beds of ivory, and stretch themselves upon their couches” (Amos 6:4), and Rabbi Yosei, son of Rabbi Ḥanina, says in explanation of this verse: These are people who urinate naked before their couches.

And Rabbi Abbahu ridiculed this interpretation and said: If so, if this was their sin, is this what is written: “Therefore now shall they go captive at the head of them that go captive” (Amos 6:7)? Could it be that because they urinated naked before their couches that they go captive at the head of them that go captive? That act is admittedly distasteful, but it is not so severe a transgression to warrant such a punishment.

Rather, Rabbi Abbahu says: These are people who eat and drink together, and attach their beds together, and exchange their wives with each other, and befoul their couches with semen that is not theirs. The Jewish people include the descendants of such people, who are full-fledged mamzerim.

Rav Yehuda said to Ulla: If so, what shall we do? How can we clarify which families are of unflawed lineage? Ulla said to him: Go after the silence, like the way the people of the West, Eretz Yisrael, examine: When two people quarrel with each other, they observe which of them becomes silent first. Then they say: This silent party is of finer lineage.

Rav says: The silence of Babylonia is its lineage. In other words, this is an effective method of examining a person’s lineage in Babylonia as well. The Gemara asks: Is that so? But Rav arrived at the house of the son of a vinegar strainer and examined them. What, is it not that he conducted an examination into their lineage? The Gemara answers: No, he conducted an examination into their silence. This is what Rav said to those conducting the examination: Examine whether they become silent when they quarrel or whether they do not become silent.

Rav Yehuda says that Rav says: If you see two people feuding with each other, there is a trace of unfitness in one of them. In other words, there are grounds to suspect that the lineage of one of them is flawed. Consequently, that one is prevented by Heaven from joining the other through marriage, and that leads them to feud with each other. Rabbi Yehoshua ben Levi says: If you see two families feuding with each other, there is a trace of unfitness in one of them, and that family is prevented by Heaven from joining the other.

Rav Pappa the Elder says in the name of Rav: Babylonia is healthy with regard to lineage and clear of suspicion. Mishon is dead, meaning that all its inhabitants have flawed lineage. Media is sick, and Eilam is moribund. The Gemara clarifies: And what is the difference between sick and moribund? Most sick people recover to a healthy life, whereas most of those who are moribund are destined for death. Likewise, the majority of the residents of Media had unflawed lineage, while the majority of those living in Eilam had flawed lineage.

After having determined that those from Babylonia are presumed to have unflawed lineage, the Gemara clarifies what the borders of Babylonia are with regard to this issue. Until where does the width of Babylonia extend? Rav said: Until the River Azak, which empties into the Euphrates. And Shmuel said: Until the River Yo’ani, which also empties into the Euphrates. The Gemara asks: Until where does the border extend upward, meaning northward, on the Tigris? Rav said: Until the places called Bagda and Avna. And Shmuel said: Until Mushekanei. The Gemara asks: But according to Shmuel, isn’t Mushekanei included in Babylonia? But didn’t Rabbi Ḥiyya bar Abba say that Shmuel says: Mushekanei is like the exile, meaning it is like Pumbedita in central Babylonia, with regard to lineage? Rather, Shmuel meant: Until and including Mushekanei.

The Gemara asks: How far does the border extend downward, meaning southward, on the Tigris? Rav Shmuel said: Until the city of Lower Appamya. The Gemara comments: There are two cities called Appamya, the upper one and the lower one. In terms of the lineage of their residents, one is unflawed and the other is flawed, and they are separated by a distance of a parasang [parsa]. And they are particular with regard to one another. The residents of the two cities avoid each other to the extent that they do not even loan each other fire, to prevent them from developing a closeness with each other. And your mnemonic to remember which is which is that the unfit one is that one that speaks the Mishon dialect. As stated above, Mishon is considered dead with regard to lineage.

The Gemara further clarifies: How far does the border extend upward, meaning northward, on the Euphrates? Rav said: Until the fortress of Tulbaknei. And Shmuel said: Until the bridge over the Euphrates. And Rabbi Yoḥanan said: Until the crossing at Gizma. The Gemara relates: Abaye would curse, and some say it was Rav Yosef that would curse, one who ruled in accordance with the opinion of Rav, as he held that Rav extended the border too far north.

The Gemara is puzzled by this statement: Why did he curse one who ruled in accordance with the opinion of Rav, but he did not curse one who ruled in accordance with the opinion of Shmuel? But the bridge over the Euphrates is further north than the fortress of Tulbaknei. Rather, he would curse one who ruled in accordance with the opinion of Rav, and all the more so one who ruled in accordance with the opinion of Shmuel. And if you wish, say: In fact, he cursed one who ruled in accordance with the opinion of Rav, but he did not curse one who ruled in accordance with the opinion of Shmuel, and the bridge over the Euphrates actually stood lower down, i.e., farther south. In their times the bridge was to the south of Tulbaknei, and Abaye agreed that it was in Babylonia.