1) WHO MUST EXAMINE THE LINEAGE OF HIS PROSPECTIVE WIFE?
OPINIONS: The Mishnah states that when a man wants to marry a Kohenes, he must examine her lineage four generations back.
Does this requirement apply to every man who wants to marry a Kohenes? Also, what exactly is he supposed to look for in his check of her lineage?
There are various opinions among the Rishonim about who performs this examination and how it is performed.
1. TOSFOS maintains that only a Kohen who wants to marry a Kohenes is required to perform this examination. He must examine whether there is a Chalal in the woman's ancestry.
2. The RAN maintains that every man, even a Yisrael, who wants to marry a Kohenes must perform this examination. The examination is necessary in order to clarify that there are no Mamzerim in the family.
The Ran's view is supported by the variant Girsa of the Mishnah. According to the standard Girsa, the Mishnah states that when one marries a "Leviyah and Yisraelis" he must add an additional generation to the genealogical examination. However, another Girsa reads "Leviyim and Yisraelim" (see Mesores ha'Shas and Rishonim). According to this Girsa, not only must Kohanim perform the examination, but every Jewish man must make such an examination to clarify that there are no Mamzerim in the woman's family.
3. RASHI explains (like the Ran) that the examination is intended to clarify that there are no Mamzerim in the family. However, he maintains that only a Kohen is required to perform the examination. (See following Insight.)
2) EXAMINING THE LINEAGE OF ONE'S PROSPECTIVE SPOUSE FOR "PESUL KEHUNAH" OR "PESUL MAMZERUS"
QUESTIONS: The Mishnah states that when a man wants to marry a Kohenes, he must examine her lineage four generations back. The Gemara asks that the woman should also be required to check her prospective husband's lineage. The Gemara answers that women of pure lineage (Kesheros) are not prohibited from marrying men of impure lineage (Pesulim). All of the Rishonim explain that the Gemara refers only to men who are disqualified from Kehunah and not to men who are disqualified from marrying into the general community, because the Torah clearly prohibits a woman from marrying a man with a Pesul of Mamzerus.
(a) The Gemara implies that the purpose of the examination is to verify the lineage of the spouse with regard to marrying a member of the Kehunah (i.e. to ensure that there is no Chalal in the family) and it is not for the purpose of verifying the lineage of the spouse with regard to marrying into the general community (i.e. to ensure that there are no Mamzerim in the family). Accordingly, the Gemara clearly contradicts the view of the RAN and RASHI who explain that the purpose of the examination is to clarify that there are no Mamzerim in the spouse's family (see previous Insight).
How do the RAN and RASHI understand the Gemara?
(b) According to the Girsa of the Mishnah in our texts, which states that one must perform a genealogical examination when he marries a "Leviyah and Yisraelis," why is such an examination necessary according to the view of TOSFOS, who maintains that only a Kohen is required to examine his prospective wife's lineage to ensure that there is no Pesul of Chalal (see previous Insight)? A Pesul of Chalal exists only in a family of Kohanim; there is no Pesul of Chalal in a family of non-Kohanim.
ANSWERS:
(a) RASHI (DH Lo) explains that since the Torah is lenient with regard to Kesheros who marry Pesulim (i.e. women of pure lineage are permitted to marry men who are Pesulim l'Kehunah), the Chachamim followed the Torah's precedent and did not institute that an examination be done even to check for Pesulei Kahal (such as Mamzer).
(b) TOSFOS (DH Tzarich) answers that since a Kohen must investigate his prospective spouse's lineage in order to ensure that there is no Pesul of Chalal, the Chachamim also required him to check for all Pesulim. Therefore, a man must check even when he marries a Leviyah or Yisraelis. (No such examination, for Pesulim of Mamzerus, was instituted for a Yisrael (a non-Kohen) who wants to marry a woman because, as Tosfos explains, "the Jewish people know who the Mamzerim are among them," and thus if a Pesul exists it is already known.)
3) THE KOHEN'S EXAMINATION OF HIS PROSPECTIVE WIFE
QUESTION: The Mishnah states that when a man wants to marry a Kohenes, he must examine her lineage four generations back. RASHI (DH Leviyah) explains that only a Kohen is required to perform this examination, and that the examination is intended to clarify that there are no Mamzerim in the family.
Why does Rashi wait until his comments on the second case of the Mishnah ("Leviyah") to explain the first case ("Kohenes")?
ANSWER: The PNEI YEHOSHUA explains that since the first case of the Mishnah discusses a Kohenes, presumably the examination in that case is intended to ensure that there is no Pesul of Chalal in the family. Since the examination is only for the Pesul of Chalal, it is obvious that it is a Kohen who is marrying the woman, for a Yisrael or Levi is permitted to marry a Chalal. The second case of the Mishnah, however, refers to the examination of the lineage of a Leviyah and Yisraelis, which is performed to ensure that there is no Pesul of Mamzerus (as a Leviyah and Yisraelis have no Pesul of Chalal). Therefore, Rashi must mention at this point in the Mishnah that this examination needs to be done only by a Kohen who marries a Leviyah or Yisraelis, and not by a Yisrael.
The Pnei Yehoshua explains that Rashi's reasoning is based on the principle, "Ma'aleh Asu b'Yuchsin" -- the Chachamim established stringencies to protect the lineage of Kohanim. They did not establish those stringencies for Yisraelim, who may rely on a "Chezkas Kashrus."

76b----------------------------------------76b

4) REQUISITES FOR POSITIONS OF AUTHORITY
QUESTION: The Gemara derives from the verse, "Som Tasim Alecha Melech... mi'Kerev Achecha" -- "You shall surely place upon yourself a king... from among your brethren" (Devarim 17:15), that any person who is appointed to a position of leadership must be "from among your brethren," to the exclusion of a convert.
The commentaries ask that the appointment of Rechavam as king of Yehudah contradicts the Gemara's principle. Rechavam's mother was Na'amah ha'Amonis, a convert. Since Rechavam came from a convert, why were the people permitted to appoint him as king?
ANSWERS:
(a) The KESEF MISHNEH (Hilchos Melachim 1:4) suggests a logical answer. If, as the Gemara says, the son of a Jewish mother and a father who is a convert is fit to be appointed king, then certainly the son of a Jewish father and a mother who is a convert should be fit to be appointed king, even though his mother is a convert. (The basis of this "Kol she'Ken" is that although with regard to matters of Yuchsin (lineage) the status of the son follows that of the mother, with regard to positions of authority (such as king) the son's status follows that of the father. Accordingly, if the father held a position of authority, the son is entitled to hold that position as well.)
(b) The NODA B'YEHUDAH explains that the Gemara's principle applies only to the initial appointment to a position of authority. The initial holder of a position of authority must have been born to a Jewish mother. However, once a dynasty has been established and the new king merely inherits the throne (and no new position is created), the Gemara's requirements with regard to the appointment of positions of authority do not apply.