As we have learned, the fourth perek of Massekhet Kiddushin focuses on family history, and discusses which communities had more reliable traditions of reliability. The Gemara taught that the Jewish community in Bavel was more reliable than the community in Israel or in other places in the Diaspora. On our daf Rav Yehuda quotes Shmuel as teaching that these attitudes are only the opinion of Rabbi Me’ir, but that the Hakhamim argue and rule that all Jewish communities, wherever they are found, are assumed to be reliably Jewish.
In a similar statement, the Gemara brings a baraita that discusses the status of mamzerim, “le-atid la-vo” – literally “in the future” but in this context it refers to Messianic times. According to Rabbi Yose, with the arrival of the Messiah mamzerim will become purified; Rabbi Me’ir disagrees and states that they will remain in their status as mamzerim.
The rishonim argue about the specific ruling about which Rabbi Me’ir and Rabbi Yose disagree. According to some (the Ritva quoting the Re’ah, the Ran’s understanding of the Rambam, and others) it is dealing only with cases where there is a safek mamzerut – where it is not clear whether a given family had this problem. Even though the Messiah is supposed to clarify unknown issues, Rabbi Yose believes that he will not declare which families are truly problematic. The Ramban, Rashba and others suggest that Rabbi Yose believes that the Messiah will really release mamzerim from their status.
The Ramban explains that this is done as a hora’at sha’ah – a one-time ruling made for a specific purpose – which is allowed by a prophet for a particular reason. After the arrival of the Messiah, however, all of the normal laws of forbidden relationships – and mamzerut – will remain in force. This is based on his view of the Messianic period as one when Israel will live in a state of peace, but that we will remain in a physical world and that all normative laws will still apply.