It is forbidden to sell real estate property in Israel to a non Jew. ("Bal Techonem") It is a Mitzva for a Jew to buy land/flat In Israel? (Yishuv Haaretz) What is the rule if a Jew wants to sell an apartment in Israel to a married couple, one of them a Jew, the other a non Jew? Is it a transgression since the seller, a Jew, is selling to a non Jew, or, as the seller is selling also to a Jew, he is helping another fellow Jew to fulfill the Mitzva of Yishuv Haaretz?
The Torah forbids selling a house in Israel to a Goy, "Lo Techonem" - do not give them a piece of land to rest upon. The Poskim wrote it's only if the Goy is an idol worshipper. That is why some say there is no prohibition to sell land to an Ismaelian, since the Rambam has decreed that they are not considered idol worshippers because they believe in one deity. The Chazon Ish disagrees, and says that since the Radbaz wrote in his responsa that a Jew must agree to be killed rather than convert to Islam, this means the Islamic faith is considered idol worshipping. The Netziv, in his commentary on the Torah (Behar), wrote that a Jew that must sell his house to a non Jew, even if he does not worship idols, the family has a Mitzva to try and redeem the house. If they can't, the Mitzva is on Klal Yisrael. The Gemara teaches that one is allowed to tell a Goy to to something which the Torah forbids the Jew to do. The example given is that it is permitted to tell a Goy to write (on Shabbat) a deed on property in Israel. The Ramban writes (in his Chiddushim, Perek "Rabbi Eliezer Demial") that one can't learn the principle from that example because that Mitzva is for the benefit of all of Yisrael, that the land won't be destroyed. We see in the Ramban, that the act of selling to a non Jew is considered destroying the land. For this reason selling to someone who is intermarried is forbidden as well. Rabbi Dov Lior