EFRAT, West Bank (JTA) — The reputable car dealer’s advertisement in the local paper screams “Brand New Mercedes — Only $500!”

You get excited but think it sounds too good to be true. Upon closer inspection, it is: The car dealer is offering only the hubcaps of the Mercedes for $500. If you want the whole car, it will cost the standard price. Suddenly the car dealer doesn’t sound so reputable.

You would never find such an ad because no car dealer in his right mind would make such an offer. Yet hubcaps masquerading as the car is exactly what Steven M. Cohen and Rabbi Kerry Olitzky offer in their recent JTA Op-Ed titled “Conversion shouldn’t be the only path to joining the Jewish people.”

Cohen and Olitzky bemoan that as of now, there’s only one way for a non-Jew to become Jewish — i.e. conversion — and offer an alternative they call “Jewish Cultural Affirmation.” Under this scheme, those who are not interested in Judaism as a religion, and even those who follow a different religion, could choose the Jewish Cultural Affirmation path.

To achieve this lofty status, they suggest that the candidate undertake a web-based self-study course along with undefined “experiences of lived Jewishness.” Candidates could sample Jewish topics ranging from politics to comedy to social action and text study. They then would be eligible to receive a “certificate of membership in the Jewish people,” much like my certificate from the American Legion.

As someone who is married to a convert, who has spent the better part of his professional life as a Jewish communal leader and counseled a wide range of sincere people in intermarriages who seek entry into the Jewish people, I find such a proposal shallow, impractical and offensive.

To reduce membership in the Jewish people to a shallow “cultural affirmation” completely misses the point of being Jewish. To put it bluntly, herring is not a religion.

We are a people who, despite our small size, have for 3,500 years had a critical mission in the world. As Christian scholar Paul Johnson wrote in his seminal “History of the Jews,” “The Jews stand at the center of the perennial attempt to give human life the dignity of a purpose.”

Judaism addresses the most pressing life-and-death issues, teaches us how to infuse the sacred into all of existence and presses us to strive to become a “light to the nations.” To reduce all of that to a mere cultural affirmation is to say that the most profound elements of Judaism are unimportant.

The proposal is impractical. People who wish to convert can and will do so. The myriad approaches to American Jewish life offer a range of conversion options, from traditional conversions that require years of preparation and a commitment to all of the mitzvahs, to conversions that can be completed in a matter of months with minimal lifestyle changes. If someone is uninterested in following even a minimal conversion route, why would they be interested in “affirming” a Jewish identity at all?

And just what would such an affirmation accomplish? There already are a number of non-Jews in intermarriages who are attempting to raise Jewish children, who serve on synagogue boards, and who observe some Jewish holidays with their Jewish spouses even as they celebrate Christmas and go to church. Jewish educational opportunities are readily available to them. Rabbis and other Jewish leaders often praise their efforts.

All this has happened without an affirmation process or completion certificate. Creating a new process is superfluous; it would do nothing to change the reality on the ground.

Finally, Cohen and Olitzky’s proposal is offensive. In my experience, Jewish leaders who propose novel conversion procedures almost never consult with the end users — converts themselves, who could tell them from deep personal experience what is and isn’t needed.

The responses of converts with whom I shared Cohen and Olitzky’s proposal ranged from befuddled to offended. Most of all, they just didn’t get why something like this is needed. Neither do I.

A “Jewish Cultural Affirmation” track would undermine the hard work of sincere converts who have chosen to transform their lives and souls in joining the Jewish people. To offer Jewish Cultural Affirmation as an equally viable alternative to traditional conversion is to cheapen the process of conversion itself. And if cultural affirmation is offered merely as a second-class track, then it will do nothing except sow confusion.

Given the current tenuous state of American Jewry, so-called Jewish leaders and funders no doubt will gravitate toward new schemes dressed up as “solutions” to the challenges of Jewish demography. But as the recent Pew Research Center’s survey of U.S. Jews shows, the race to water down Jewish life has only weakened it. Rather than throwing more good money after bad, we should focus instead on what makes a Jewish life worth living.

(Harold Berman, the co-author of “Doublelife: One Family, Two Faiths and a Journey of Hope,” is the former executive director of the Jewish Federation of Western Massachusetts. He and his wife, Gayle, are the founders of J-Journey.org, a support system for intermarried families who seek to become observant Jews.)