The unification of the Yisrael Beytenu and Likud parties presents a real danger to the Likud's traditionalism and social policies. The danger is that Avigdor Lieberman and his party will obscure Likud's traditional character, rendering it anti-religious and anti-social.

In the outgoing Knesset, Shas has time and again had to fight off proposed laws by Yisrael Beytenu that would have utterly cheapened the process of conversion and joining the Jewish people. It wanted insta-conversion, as if joining the Jewish people was no greater a matter than signing up for a health club. Yisrael Beytenu spearheaded untiring legislative efforts to introduce civil marriage to Israel, a move that in our view would be tantamount to assimilation and the destruction of our forefathers' Judaism.

I concede that civil marriage is seductive to many members of the public. But for the religious community it constitutes a real threat to the basic values, identity and lifestyle that preserve us as a nation and society.

Between 2003 and 2006, we suffered the bitter experience of a government with no ultra-Othodox parties. Senior Likud politicians now admit they are considering, or even, God forbid, hoping, to repeat that experience. This not only threatens Jewish identity, but social programs as well. It is Shas' role at present to warn of the potential collapse of Israeli social solidarity and compassion. Values and systems that preserve us as a society and a people are in danger of destruction.

That is why the Shas leadership this week sent Prime Minister Benjamin Netanyahu — our nominee to establish a government — a declaration that we hope he will sign. The declaration is a commitment that his government will preserve the state's Jewish foundations. If it wasn't for the hostile takeover of Likud by Yisrael Beytenu, or Livni and Lapid's obsession with an ultra-Orthodox-free government, it is doubtful that such a step would have been necessary.

It is in this context that we should judge the controversial campaign commercial broadcast by Shas over the past few days. The point of the clip was to raise a difficult issue in a satirical and lighthearted way. The commercial does not contain an ounce of racism, but rather a ton of concern for Jewish identity. Conversion is not a convention of clowns or a game of make-believe. This was the message of the commercial and nothing else.

The commercial is not generalizing to include all new immigrants from the former Soviet Union, certainly not those who are Halachic Jews. We should mention that the Shas electorate includes many voters from the former Soviet Union. Shas politicians come from places like the Caucasus and Bukhara (MK Amnon Cohen) as well as from Georgia (MK Avraham Michaeli). It is nonsense to accuse Shas of racism and a sad testimony to how lightly the term is thrown around.

Rabbi Ovadia Yosef, one of the greatest Halachic minds of his generation, and Chief Sephardi Rabbi Shlomo Amar have for years made efforts to solve the conversion conundrum. They have done this for the sake of the Jewish future and Jewish solidarity. In doing so, they have brought to bear the Halachic principle of “koach dehitra adif” — that one should try to be lenient when presented with a divided opinion. Yes, we should definitely try to be lenient, but not to the point where we give up on basic Halachic principles.

Yitzhak Sudari is a member of the Shas election campaign staff.