The following article originally appeared in the Forward Newspaper Online, June 10, 2005. Reproduced with permission from the author.

When you write a book called Why the Jews Rejected Jesus" and make your e-mail address available on a Web site bearing your name, as I've done, you are going to get a lot of e-mail from strangers. Some of it will be friendly, some hostile and some just heartbreaking. In the last category, I place the many communications I've received from messianic Jews — a correspondence that has made me question the longstanding Jewish policy of shunning such people.

Messianic Jews attend places of worship where traditional Jewish religious observances are practiced, but they also revere Jesus as the messiah and as God incarnate. As of 1995, there were 30,000 of them in the United States, according to the World Christian Encyclopedia, published by Oxford University Press, or 160,600 globally in 2000. They belong to "messianic Jewish" denominations whose membership, according to the same source, range up to 90% born gentiles, with only 10% born Jews.

You hear little about them because the Jewish community denies their leaders and organizations any recognition. Ordinary messianic believers feel the painful effects of the quarantine.

A messianic Jew named Bob wrote to me of being ejected from synagogues in Kansas City, New York's Upper West Side and Singapore. Susan from San Francisco told of the "Conservative synagogue in which the president of the congregation and the cantor gave the rabbi an ultimatum: Kick me out or they would leave. I honored the rabbi's request that I not 'evangelize' in the synagogue. But my membership dues were returned and I was no longer welcomed." Michael, now living in Harrisburg, N.C., recalled being spat on while riding the Long Island Railroad.

Is the quarantine policy necessary? Is it fair?

It may be necessary. After all, passion can be persuasive; and followers of messianic Judaism are passionate to share their faith in a manner you don't often encounter in liberal Jewish denominations — though you do in Orthodox Judaism. The messianic movement poses a special challenge to the continuity of Jewish belief. Ostracism is also a spur to rethinking your beliefs.

But what is necessary may not be fair. Do messianic Jews depart from Judaism in any way that alone sets them apart from other Jewish denominations?

Theologically, messianic Judaism is a hybrid, with doctrines that run counter to the Hebrew Bible — for example, the prophets' faith that the messiah will preside over a world so radically changed that nobody will need to ask if he's come — and other beliefs contrary to the New Testament. The latter, calling Torah "obsolete," a "curse" and a "captor" (Hebrews 8:13, Galatians 3:13 and Romans 7:6), dispenses with the Jewish observances that messianics cherish.

Many Jews criticize messianic spokesmen for blurring the distinction between Judaism and Christianity. But is this any different from mainstream Jewish leaders who — on issues ranging from homosexuality to abortion and euthanasia — blur the equally sharp divide between traditional Jewish values and the values of secular liberalism?

Ah, you say, messianic Judaism is deceptive in doing this? Well, no more so than those Jewish groups that campaign for gay rights while disguising the fact that Jewish scripture unambiguously forbids homosexual intercourse (Leviticus 18:22).

Other Jews argue that messianics have ceased to be Jews because they revere Jesus as God incarnate, or because they worship a triune Deity. From the perspective of Judaism as it has been practiced for three millennia, there is indeed a problem in imagining God as taking a bodily form (see Deuteronomy 4:15) or as comprising distinct persons (Deuteronomy 6:4). But other beliefs constituting no less serious a departure from biblical tradition are smiled upon in our community. For instance, our liberal denominations reject the ancient faith that the Torah was received by Moses from God, thus reducing much of Judaism to mere folklore.

The gravity of this is evident from the teachings of Maimonides. In his encyclopedic "Mishneh Torah," he lists 24 categories of people who may forfeit eternal life. One is a Jew who attributes bodily form to God. One is a Jew who believes in multiple deities. Another is one who denies that even a single word in the Torah comes from God.

To revile messianic Judaism while embracing Jewish movements that deny the revelation of the Torah at Sinai, then, makes little sense.

The irony is that messianic Judaism stands out by affirming the divine authorship of the entire Torah. When I debated a Conservative rabbi recently at the University of Judaism in Los Angeles, a messianic Jew in the audience thanked me afterward for "speaking up for what the Torah says instead of what is 'politically correct' in Reform and Conservative Judaism."

This same woman lamented, "We are often treated as 'pariahs' by other Jews." Is that fair?

There is a further, practical objection to messianic Judaism. One may reasonably argue that Jewish belief in Jesus acts as a corrosive, an acid upon Jewish existence. There has never been a viable "Jewish Christianity" that didn't ultimately disappear into the wider gentile world. Yet secularism has done a better job of decimating our ranks than has any other religion, and you don't hear many Jews speaking out against secularism. Fair?

Certainly it is understandable that some Jews feel as they do about these Jewish Christians. For many, there is something stomach-churning about a Jew who embraces a faith with a centuries-long record of treating his own ancestors in cruel and humiliating ways.

And yet what is understandable, just like what is necessary, also isn't necessarily fair. After all, we live in America with her unique philosemitic Evangelical Christian tradition. To imagine American Christianity, of which messianic Judaism forms a part, as if it were indistinguishable from medieval European Christianity is historically inaccurate.

No, I'm not trying to be judgmental about anyone's beliefs. There is value, however, in shining light on an area — of interest to believers in Judaism as to believers in Jesus — that has been wrapped in murkiness and unreason. Let there be light.