The Jews are not a race. There is no genetic code passed from either mother or father to the child that makes that child a Jew. Although one cannot convert to become an Oriental or a Black, one who converts to Judaism becomes a Jew.
When the non-Jewish world makes the claim that
one who was Jewish but converts to Christianity can retain the "Jewish
culture and ethnicity," one must ask, "which Jewish culture?"
and "which Jewish ethnicity?" The culture and ethnicity of a Jew from
Morocco has little in common with the culture and ethnicity of a Jew from
Eastern Europe. Yet both are Jews because their
faith, their Judaism, is the same.
And just as many people convert to Judaism, and they become Jews, those who convert out of Judaism are no longer Jews.
The Biblical basis for this is I Kings 18:21.
Elijah the prophet asked Jews who were beginning to slip into the worship
of Baal, "How long will you go limping with two different opinions? If
the
G-d of the Jews is G-d, follow Him! but if Baal is Gd, then follow
him!" There is a choice to make. That choice is between one faith or the
other; you cannot believe in two opposite, mutually
exclusive ideas simultaneously.
A Rabbi named the Hai Gaon, the last of the Gaonim with any authority (as quoted by Adret, in Responsa, VII #292) stated that a Jew who converted out of the faith was no longer a Jew. This idea was shared by numerous rabbis, which can be seen in the Responsa literature of Simon ben Zemah of Duran, Samuel de Medina, Judah Berab, Jacob Berab, Moses ben Elias Kapsali, and others in the Middle Ages. In fact, Moses Isserles demanded a formal conversion back to Judaism for those who converted out of Judaism, but who then wanted to return to Judaism. He demanded ritual immersion (mikvah) and repentance before a court of three (beit din). You will see this also in other Responsa literature: Radbaz, Responsa III, 415; Moses Isserles to Yoreh Deah 268.12; and Hoffman, Melamed Leho-il II, 84. See also Maimonides, Hilchos Mamrim Perek 3, Halacha 1-3, as well as in Maimonides's Mishnah Torah, Avodat Kochavim 2:5.
It was only after the experience of the Marranos, Jews who were forced by the Church to convert to Catholicism (mostly in Spain), but who secretly practiced Judaism, that the Rabbis stated that one who converted involuntarily out of Judaism did not have to convert back to Judaism. This assumes that because it was done out of force; the Jewish neshama (soul) never really left the Jewish faith (through free will). This also concerns only those who wish to return to Judaism. It says nothing about those who remain Christian.
Nor is it true in the case of anyone else, anywhere else, converting to Christianity today. In the modern world, no one is given the three choices: leaving the country of their birth, death, or conversion to Christianity, as the Jews of Europe were given during the Middle Ages, and which gave reason to the leniency.
Modern Israel has a law called the Law of Return. This means that, because Israel is the Jewish homeland, one who is Jewish can come to Israel, and immediately become an Israeli citizen, as one coming home.
Let us venture into some personal accounts of why a Jesus-believing individual born Jewish is no longer Jewish after the acceptance of a new religion and a new god or messiah.
Daniel Rufeisen was born Jewish, of two Jewish parents. Because of the nazi persecutions, his parents hid him with a couple who were Catholic. But, they raised him as a Catholic, and he became a Catholic priest. Father Daniel, aware of his parents' heritage, went to Israel and applied to become a citizen of Israel under the Law of Return. The Israeli Supreme Court denied his application, stating that, since he converted, he was no longer a Jew. He had to wait the customary time for any other non-Jew to become a naturalized Israeli citizen, just as in the United States, one has to wait 6 years in order to become a naturalized United States citizen.
Please note that the family who hid Father Daniel did not follow the wishes of Daniel's parents. They wanted to save their child as a Jew, but, as a Jew, Daniel was lost.
More recently and quite similarily, the same thing happened to a "Messianic Jewish" couple. The Beresfords from South Africa tried to become citizens of Israel under the Law of Return. They were denied on the same basis as Father Daniel. It is interesting to note that the man leading the fight against the Beresfords for the Israeli Department of Immigration was an Orthodox rabbi and member of the Orthodox Israeli political party known as Shas.
Furthermore, this is the attitude of many Orthodox rabbis today. Orthodox Rabbi Aryeh Kaplan, writing for the Union of Orthodox Jewish Congregations of America, for the National Conference of Synagogue Youth, the Orthodox Youth Group, in his book "The Real Messiah," on page 21 wrote: "A Jew who accepts Christianity might call himself a 'Jewish-Christian', but he/she is no longer a Jew." Rabbi Kaplan refers to Maimonides' Mishneh Torah, Avodat Kochavim 2:5 in support of his statement.
As an act of leniency, however, few rabbis today ask the ex-Jew returning to Judaism to go through any ceremony of conversion. This might be a "stumbling block before the blind," before those who wish to return. So long as one remains a Christian, one is no longer a Jew. But if one wishes to return to Judaism, the return is made easy as an act of compassion.
Similarly, so long as one believes that Jesus was anything more than a human being who lived and died around 2,000 years ago, that person cannot convert TO Judaism, and become a Jew. The two faiths of Judaism and Christianity are simply mutually exclusive and incompatible.
You were born Jewish, but believe in another religion, and want to be recognized as a Jew? That is simple! Simply reject your other belief system(s), and come home to the truth and beauty of Traditional Judaism.
Rabbi Federow's e-mail address is federow@blkbox.com