I have heard that the aseres hashvatim are across the sambatyon but this gemara says that they have become meshumadim is the version i heard right? please explain in length what the sambatyon is. Thank you in advance for all your hard work in spreading torah may you be zocheh to spread torah with comfort for a long time
F. Lax
Thank you for your warm words. Here is a brief answer.
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More at length:
Our Gemara is not really saying that they have become Meshumadim, but rather that they have mingled with the Nochrim and do not always keep the laws of Arayos. Their children have the status of Mamzerim because they married their close relatives (see Rashi 17a, DH "l'Fsol"). However, whether or not they will end up coming back is an argument amongst both the Tana'im and Amora'im. Most famously, the Mishnah in Sanhedrin (in Chelek 10:3) quotes an argument between Rebbi Akiva and Rebbi Eliezer regarding whether or not they will rejoin Klal Yisrael. The Medrash Rabah in Bamidbar (16:25) says they will return from beyond Sambatyon, the famous river that supposedly stops flowing on Shabbos. Much has been written about this river, people who have looked for the lost tribes, and people who claimed to have come from beyond Sambatyon. The most famous of these was Rebbi Eldad Ha'Dani, who during the period of the Rishonim brought with him a Sefer on Hilchos Shechitah and Treifos.
All the best,
Yaakov Montrose