The book of Leviticus, in its catalogue of forbidden unions, says nothing about marriage between uncles and nieces. The rabbis of the talmudic period allowed and even approved of such marriages, at least between a man and his sister’s daughter; they seem to have differed on the question of marriage between a man and his brother’s daughter, while agreeing that it was not forbidden by the Bible. Later, a small number of medieval rabbis moved to prohibit any uncle-niece marriage at all, and recent scholars have discovered ancient manuscript evidence that both Sadducees and the Qumran sect forbade such unions. Rudolph Klein explains:

[The 20th-century rabbi and academic scholar] Saul Lieberman argues that the talmudic rabbis classified marrying one’s niece as a positive deed specifically in order to counter the Sadducean view that marrying one’s niece is biblically forbidden. He notes it is the rabbis’ way to take things that are simply “allowed” by the Bible and encourage people to do them in order to undermine sectarian heretical views.

Interestingly, [the 14th-century rabbinic scholar] Ishtori ha-Parḥi notes that the Sadducees were not innovators in banning marriage to a niece; [he claims that] they adopted the prohibition from the Samaritans, who took the idea from the Arabs. Later, the Karaites also followed suit and outlawed uncle-niece marriage.

Ron Ben-Yishai explains Hamas’s current calculations:

Strategically speaking, Hamas is hoping to add more and more days to the pause currently in effect, setting a new reality in stone, one which will convince the United States to get Israel to end the war. At the same time, they still have most of the hostages hidden in every underground crevice they could find, and hope to exchange those with as many Hamas and Islamic Jihad prisoners currently in Israeli prisons, planning on “revitalizing” their terrorist inclinations to even the odds against the seemingly unstoppable Israeli war machine.

Chances are that if pressured to do so by Qatar and Egypt, they will release men over 60 with the same “three-for-one” deal they’ve had in place so far, but when Israeli soldiers are all they have left to exchange, they are unlikely to extend the arrangement, instead insisting that for every IDF soldier released, thousands of their people would be set free.

In one of his last speeches prior to October 7, the Gaza-based Hamas chief Yahya Sinwar said, “remember the number one, one, one, one.” While he did not elaborate, it is believed he meant he wants 1,111 Hamas terrorists held in Israel released for every Israeli soldier, and those words came out of his mouth before he could even believe he would be able to abduct Israelis in the hundreds. This added leverage is likely to get him to aim for the release for all prisoners from Israeli facilities, not just some or even most.