The Non-Jew in Jewish Law
Rabbinic authorities have used different arguments to redress inequities in the way halakhah treats non-Jews.
The Talmud reports the following story:
"The Roman government sent two officers to the sages of Israel to learn the Torah. They read it, they read it again, and then a third time. As they left they said, 'We have studied all of your Torah carefully, and found it to be the truth, with this exception: if a Jew's ox gores a gentile's ox, there is no liability, but if a gentile's ox gores a Jew's ox, whether the ox has a history of goring or not, full compensation has to be paid…" (Bavli Bava Kamma 38a).
The story of Romans visiting the Jewish sages is a typical narrative device designed to present how the Talmudic authors felt they ought to be seen by outsiders. In this story, the Roman officers see Jewish law as generally fair. The Talmud, however, places a sharp criticism into the mouths of the Romans. The Torah says, "If one man's ox gores his neighbor's and it dies…" (Exodus 21:35). The Romans argue:
"If the word 'neighbor' excludes gentiles, then when a gentile's ox gores a Jew's ox, he should be exempt from damages. If 'neighbor' includes gentiles, then the Jew should be obligated to pay damages when his ox gores one belonging to a gentile."
In a parallel story in the Talmud Yerushalmi, Rabban Gamaliel responds to the criticism (there concerning whether property stolen from a non-Jew could be used) by reversing the law--and forbidding the use of an object stolen from a gentile--lest the law cause God's name to be profaned (Talmud Yerushalmi Bava Kamma 4:3, 2c).
In general, when the Torah states a law applying to one's "neighbor," the rabbis understand the law as applying to Jews and not to non-Jews. This, then, is the underlying question: when do Jews relate to non-Jews as neighbors, and when do they not?
Laws to Separate Jews from Idolatry
Jewish law tries to separate Jews from gentiles, in order to prevent Jews from adopting idolatrous behaviors. Extensions of the dietary laws limited social interactions. Jews are not allowed to leave their wine with idolaters, lest it be used for idolatry (Shulhan Arukh Yoreh Deah 128:1), and food cooked by non-Jews is also prohibited (Yoreh Deah 113:1ff.). There are exceptions and loopholes, but the general force is to discourage interaction between Jews and non-Jews.
These laws had serious ramifications in the Middle Ages, when most authorities considered the Christian belief in the Trinity as idolatrous. The Mishnah prohibits any commerce with idolaters prior to their holidays (Mishnah Avodah Zarah 1:1), whichfor Christians is every Sunday. Jews were also prohibited from engaging in partnerships with idolaters, lest the idolaters be encouraged to make oaths to their gods. Both of these laws posed economic challenges to medieval Jews. Jacob Katz, in his landmark study, Exclusiveness and Tolerance, identified three distinct approaches to these challenges.