[Regarding this we find in] Avodah Zarah 20a: “You must not give them any consideration ” (Deut. 7:2): Do not give them a foothold [“chanayah”] on the land. Alternately: Ascribe to them no charm [“chen”. Rashi: “Do not say, 'How fine this non-Jew is!'”]. Alternately: Give them no free [“chinam”] gift. Later on the Talmud concludes, “All are valid.” An additional restriction appears in Rambam, Hilchot Avodah Zarah 10:3,4: We do not sell them houses and fields in Eretz Yisrael... neither do we lease fields to them... Why were our sages strict regarding fields? It is because [leasing them to non-Jews] has two [negative results]: It diminishes the tithes and gives non-Jews a foothold on the Land. We are allowed to sell them houses and fields outside the Land because it [any foreign land] is not our land. It is thus clear that there are two reasons for the Torah prohibition against selling houses, or even leasing fields, to any non-Jew, even if he be one of the righteous gentiles [a ger toshav].
Rambam mentioned both in discussing the prohibition against leasing fields (Hilchot Avodah Zarah 10:4): “It diminishes the tithes (1) and gives them a foothold on the land (2).”
(1) Since Eretz Yisrael is holy and we are duty-bound to sanctify its soil through tithes (besides all the other mitzvot that are dependent on the land), how can we dare sell or lease land to any non-Jew? A non-Jew is not bound by tithes, and by our action, we diminish the scope of the mitzvah, and, so to speak, the holiness that is thereby added to this soil.
(2) A non-Jew, by buying or renting land in Eretz Yisrael, takes a portion of the land and has a sort of ownership over it, and it is forbidden to give him this foothold. What, after all, is this “foothold”? Surely it is the feeling in the non-Jew's heart that he has found a place to live, a place to call his own.
Rambam wrote explicitly (Ibid.): Why do we not sell to them? It says, “Do not give them any consideration” (Deut. 7:2). Give them no foothold on the Land. As long as they have no land, their residence there is temporary. In our own time, Rabbis have struggled over this, and for various reasons, to our chagrin, some have ruled that it is permissible today to sell fields and houses to non-Jews. I have no doubt whatsoever that they are erring regarding the great foundation of the Land and People of Israel, and that there is no difference at all as far as giving non-Jews a foothold in the land and ascribing to them charm, between the seven nations, plain idolaters and ger toshav. [The difference between these groups is that a ger toshav is essentially permitted to live in Eretz Yisrael, though without owning land, without a “foothold”, whereas members of the seven nations or those equal to them today (unless they submit to very specific conditions) and all plain idolaters may not live in Eretz Yisrael at all.]
“Ascribe them no charm”: From the verse, “These are the laws that you must set before [Israel]” (Ex. 21:1), we derive that even if non-Jews judge the same way as Jews, it is forbidden to use their courts. The reason is that the very acceptance of the non-Jew or his laws, even if they are like Torah law, is a chilul Hashem. A Jew is forbidden to accept upon himself either non-Jewish law or a non-Jewish judge, as it says, “Their powers are not like our Mighty One, although our enemies sit in judgment.” Rashi comments (Ex. 21:1), “When our enemies sit in judgment, it testifies to the superiority of their deity” [or religion, or value system, as we encounter today in the form of Arab Muslim judges in Israel or in the case of Jews outside Israel using non-Jewish courts even in internal Jewish matters!] Here is decisive proof for the prohibition against appointing a non-Jewish judge over Israel, even if he judges according to Torah law.
Some have sought to approve non-Jews serving in positions of authority over Israel, and they bring proof from the Mishnah (Avot 1:10): “Shemaya and Avtalion received the oral tradition from them [Yehuda ben Tabai and Shimon ben Shetach].” In other words, Shemaya was the prince and Avtalion the head of the Sanhedrin, despite their having been converts, and how could they have held these posts when according to the Talmud and poskim it is forbidden to appoint a convert [meaning a ger tzedek, a complete convert to Judaism] to a position over Israel. HaKnesset HaGedolah answers this (Choshen Mishpat, mahadura kamma, siman 7), saying that if Israel accepted a convert over them, then it is permissible.
Based on this, in this orphan generation, reeling from fear of the nations and an inferiority complex regarding what Hellenists will say about the holy laws separating Israel and the nations, some have declared that there is no prohibition against appointing even non-Jews (and not just converts) to positions over Israel, if Israel accept them upon themselves. G-d forgive them! According to their opinion, can a non-Jew be appointed even king or prince if he is accepted? Can an elected government have a non-Jewish majority, or even a number of non-Jews that will enable them to place their imprint on the character of the state? And if one non-Jew can be appointed, why not a majority or such a large number that they will be able to decide on such issues as who is a Jew, Sabbath desecration, pig farming, mixed marriages, missionizing or the dissemination of the false, alien culture – and all in the name of the alien, abominable concept of “democracy”? Let the heavens be astonished! Shall those who condone this not understand the gravity of their error?
If our sages permitted the appointing of a convert by mutual agreement, that is because the law that a convert is unfit for positions of authority over Jews is just based on an exposition brought by our sages and is not explicit in any verse. Yet, the restriction forbidding the non-Jew from positions of authority is explicit in a verse and serves to separate him from Jews. It is part of his servitude and constitutes a declaration that he has no right to authority over G-d's holy people. A convert, by contrast, is a Jew in every way and is restricted only because authority over Israel must be held exclusively by the elite and not by those who were non-Jews and have now converted. Therefore, perhaps we could say, with some reservations, that because a convert has accepted the Torah and is a Jew in every way, and there is no reason to separate him from Israel, him being part of Israel and keeping the mitzvot, then if the community agrees, he may serve in positions of authority. Yet, none of this has any connection to the non-Jew, whose reason for being unfit for positions of authority over Israel differs entirely. The non-Jew is not a part of the Jewish People. He has no portion in the Land, and no one can seriously claim that he can be granted authority over Israel.
If G-d demanded our separation from the nations, why allow non-Jews to live in the Land? The answer is that G-d wished to eradicate idolatry as much as possible, thereby sanctifying His name among the nations so that they would accept the yoke of His kingdom. If a non-Jew sincerely wishes to be a resident alien (ger toshav), to abandon idolatry and undertake the seven Noahide laws, thereby sanctifying G-d's name among the nations, better that he should do this and live in Eretz Yisrael than to live outside the Land as an idolater and profane G-d's name. Clearly, however, all this applies only if he accepts conditions guaranteeing that he remain isolated from Israel and ensuring his understanding that Eretz Yisrael is the exclusive land of the Jewish People and that he has only the right to reside there. A non-Jew does not become a ger toshav until he stands before a Jewish court and accepts the seven Noachide laws. As Rambam wrote: “Whoever accepts them is the person called a ger toshav throughout the Talmud, assuming he accepts them before a court of three” (Hilchot Melachim 8:10). It certainly does not suffice for him to reject idolatrous beliefs or actual worship, if it is not accompanied by a court declaration. [Regarding this] Ritva ruled (Makot 9a): A ben-Noach [as opposed to a ger toshav, see above] is one who did not undertake these mitzvot in Jewish court, yet we know that he keeps them on his own... We are not commanded to sustain such a person... The stam goi [plain non-Jew] is one who does not keep the seven mitzvot [and who is not permitted to live in Eretz Yisrael under any circumstances]. From these rulings it emerges that only a non-Jew who undertook before a Jewish court to keep the seven Noachide laws is called a ger toshav, and only he can be allowed to live among us in Eretz Yisrael. This implies that a non-Jew must accept the seven mitzvot upon himself as being part of the Torah [and not for any other reason]. That, after all, is why he appears before the Jewish court.
Never forget the following rule: With all we have said about the non-Jew who undertook [...] the seven Noachide laws being called a resident alien (ger toshav), and being allowed to live in the Land, there is no duty applying to us whose omission renders us sinners. Rather, the law is just a dispensation, to make it easier for the non-Jew to come closer to the Divine truth. In other words, we are allowed - not obligated - to let such a non-Jew live in Eretz Yisrael. If, for any reason (i.e. security precautions), we fear danger of deception, then we are certainly permitted and required to forbid every non-Jew, even the resident alien (ger toshav), to live in the Land. (after all, even converts were rejected during certain periods for certain reasons).
You shall observe the commandment, and the decrees and the ordinances that I command you today, to perform them. (Deut. 7:11)
Compiled by Tzipora Liron-Pinner from 'The Jewish Idea' of Rav Meir Kahane, HY"D
[As an afterthought: This also highlights an aspect of the current conversion law debate: Recognizing people as “Jewish” who underwent non-halachic “conversions” would over the course of time lead to the presence of a new category of non-Jews in Israel who are disguised as Jews and who pass this status on to their descendants. This would cast a shade of doubt on all converts, even on those who underwent a valid, halachic conversion. As the non-halachic movements, Reform and others, don't recognize the Divine origin of the Torah, those who “converted” to them, do not even qualify halachically as a ger toshav. I acknowledge that there are well-meaning people who for a variety of reasons underwent initially a non-halachic “conversion”. They should, in my opinion, be given the chance to correct this mistake and undergo a valid, halachic conversion in Israel. I was given this chance and I used it. However, those who insist upon clinging to a non-halachic “conversion” must be made aware of their status as non-Jews and be separated from Israel.]