Answer: According to the Torah, the goal of creation is to bring all the created beings to adhesion with the Creator. Adhesion is attained by the correction of the ego to love, as it says: “love thy friend as thyself; this is the great rule of the Torah.” Jews are a nation that has to fulfill the Creator’s rule first, and then teach it to the whole world. This is what the wisdom of Kabbalah says and what I believe. I will refer to the following items:
The source of the prohibition
Contemporary Rabbi Yoel Shwartz, says: a non Jew who studies the Torah commits a sin. It is forbidden for Jews to teach the gentiles the Torah. The prohibition for a gentile to study the Torah is first mentioned in the Babylonian Talmud: Rabi Yochanan said “A gentile who studies the Torah should die, as it says, ‘Moses commanded us a law, an inheritance of the congregation of Jacob.’ (Deuteronomy 33:4). This is our legacy and not theirs!” (Sanhedrin 59:1).
“It is forbidden to teach the Torah to gentiles” (Hagigah, 13:1). Rambam quotes Rabi Meir as the authority, “a gentile who studies the Torah should die, and they are allowed to study only what is related to the seven commandments” (Mishna Torah, the Laws of Kings 10:9).
Shmuel Abuav who lived in the 17th century said: The Christians use the Jewish writings in order to prove the reliability of their faith and it is therefore forbidden to teach them the Torah.
However, there are quite a few examples of famous rabbis who taught the Torah to gentiles. A teacher of the German researcher of Judaism Johan Raichlin was the composer of the classic commentary of the Bible, “Our Story.” Such people knew the Halacha and couldn’t consciously break the rules of the Torah!
Rambam said that it forbidden to teach the Torah only to the gentiles who don’t acknowledge the Godly nature of the Torah. “We can teach the Torah to Christians because they believe that our Torah was given to us by God through our teacher Moses (Pe’er Ha’Dor, 38).
The Talmudic scholar of the Middle Ages Menachem HaMeiri said that if a gentile studies the Torah out of curiosity, it is not forbidden to teach him. This became relevant in modern times when the question of whether it is allowed to teach Jewish matters at universities arose.
The American Rabbi Jacob Weinberg said that when a gentile studies the Torah for academic purposes, there is no prohibition to do so. He was a lecturer at the non-Jewish University of Giessen in Germany who taught the Torah and the Talmud.
In the 19th century the Lithuanian, Rabbi Israel Salenter dreamt of turning the Talmud into one of the subjects at non-Jewish universities and at that time only gentiles studied at universities.
Teaching mixed groups
Halacha authorities such as Jacob Weinberg, Isaac Klein, Moshe Finestein, Ovadia Yoseph and others claimed that the prohibition to teach the Torah refers only to a group that is totally non-Jewish, but it is possible to reach the Torah to a Jew in the presence of gentiles even if they can also study.
According to Rav Finestein a non-Jewish slave of Raban Gamliel, Tabie, is mentioned in the Talmud as a great expert in the Torah. Tabie acquired his knowledge when he was present in the lessons given by Raban Gamliel to his Jewish students. The sages of the Talmud had no problem teaching the Torah even when there were non-Jews among the listeners.
The seventh Rabbi from Lubavich welcomed the study of the Torah by modern means of communication and in modern languages although this form of teaching included many non-Jewish readers and listeners.
Constraint: The prohibition to teach the Torah to non Jews is cancelled if there is a government decree because disobeying such a decree might endanger the Jewish community. Today any attempt to separate Jewish and non-Jewish students in academic institutions might arouse negative responses. Thus a Jewish lecturer may believe that he is constantly under the government decree which nullifies the prohibition to teach the Torah to non-Jews.
Is there a prohibition to teach the Torah to non-Jews?
Rav Isaac Ilinburg (1550-1623) noticed that his Italian colleagues taught the Torah to non-Jews. He emphasized that neither Rambam nor other Halacha authorities ever mention the prohibition to teach the Torah to non-Jews.
He thus concluded that parallel expressions in Masechet Hagigah are not the Halacha at all. He said that he was not ready to publicly declare that only for fear of the reactions of his colleagues.
Rav Arie-Leib Ginsburg (1695-1785), the author of The Lion’s Roar, holds the same opinion.
History provides us with plenty of examples of non-Jews who studied the Torah and used their knowledge not in order to harm the Jewish nation but in its favor, in order to contradict false accusations against Judaism.