The bill, which emerged from a stormy session of Prime Minister Benjamin Netanyahu’s government and has been bitterly disputed across Israel, is likely to be softened before it comes to a vote in the Parliament. In any form, it should be defeated. At best, the law would have no useful effect; at worst, it would seriously antagonize an already seething Arab minority and erode Israel’s standing among democratic nations.

Israel’s courts and laws have consistently defined Israel as “Jewish and democratic,” giving equal weight to both, and on paper, at least, the Arab Israelis who constitute about a fifth of the population have full rights. To go back and emphasize nationality and religion in defining the country, moreover, runs counter to the long-term movement among liberal democracies toward a more inclusive vision of a state.

A nationalities bill has long been sought by Israel’s right wing, and the initial draft they produced downgraded Arabic from an official language to one with “special status.” That and other antagonistic elements are likely to be dropped from the version that reaches Parliament.

But in this time of high tensions and violence between Jews and Arabs, incited by competing claims to the sacred site in the heart of Jerusalem — called the Temple Mount by Jews and Noble Sanctuary by Muslims — any measure that claims a pre-eminent status for Jews can only add fuel to the fire.

Mr. Netanyahu says that the nationality bill is necessary because there were so many challenges to Israel’s existence. But it is hard to see how a law would put a stop to that. There is also speculation in the Israeli press that the prime minister has been pushing the bill as a political sop to right-wing members of his fractious coalition — indeed, the cabinet vote was split 14 to 6 along ideological lines, with two centrist parties opposing it.