Demai, Chapter Six, Mishnah Ten
In the previous mishnah we learned that if a chaver and an am haaretz inherited from their father, they cant swap one type of produce for another. In this mishnah we learn about a gentile and a convert who come to inherit from their father. In this case, the convert can take all of the parts of the inheritance that are permitted to him and give his non-Jewish brother all of the idolatrous objects and wine, both of which are prohibited to the Jew. In our explanation below we shall discuss why the two cases are different.
1) A convert and a gentile who inherited [the property of] their father, a gentile: he (the convert) can say [to his brother the gentile]: You take the idols and I will take the money, or: You take the wine and I will take the produce.
2) But from the time [that any part of the inheritance] came into the possession of the convert, he is forbidden [to say so].
Section one: The convert can tell the gentile that he will take the permitted part of the inheritance and that the gentile will take the parts of the inheritance that are not permitted to Jews. This includes the idols and the wine, which a Jew may not use in case it had been use as an idolatrous libation. This is permitted even though this is like swapping one type of produce for another, which we learned in yesterdays mishnah did not work in the case of an am haaretz and a chaver. The key difference here is that according to Torah law, a convert does not inherit from his gentile father because when he converts, he loses his biological ties to his former family. The rabbis, nevertheless, decreed that the convert would inherit, probably so as not to deter him from converting. Since his inheritance is not from the Torah, the items that he takes from his fathers estate are looked at as if they are not his until they actually come into his possession. Therefore, the convert is not actually swapping idolatrous things that he owns for permitted things, which would be forbidden to do. Rather he is just taking some of his fathers estate and giving other parts of it to his gentile brother.
Section two: Once he has actually taken something forbidden such as an idol into his possession, he may not swap it with his brother, because a Jew is forbidden from deriving benefit from anything that was used for idolatry. Were he to swap idols for money, he would be deriving benefit from idolatry.