Israel's , but now they have been pushed into opposition by a they fear will put secular values before theirs.
After years in power , the ultra-Orthodox parties are "experiencing a deep crisis", said Peggy Cidor, a journalist at the Jerusalem Post newspaper.
In Israel, where Orthodox practise is for Jews the basis for state laws in matters such as marriage, divorce and death, a constant battle rages over religion's grip on public life.
Many ultra-Orthodox "are terrified by this new government" which appears to them as "catastrophic", said Cidor, an expert on Haredi society, the Hebrew name for ultra-Orthodox Jews who constitute some 12 percent of Israelis.
In Israel's latest general election back in March, the two ultra-Orthodox parties - and United Torah Judaism (UTJ) - won 16 of parliament's 120 seats, and both backed Netanyahu's failed bid to remain as prime minister.
The parties were banking on remaining in the coalition arrangements they had been part of for most of Netanyahu's 12 unbroken years of rule.
Loss of power and funding
But their support was not enough -- and Netanyahu on Sunday was toppled by an ideologically divided coalition including, for the first time in Israel's history, an Arab party.
Yair Lapid, a centrist and the architect of the new government, formed an improbable "change" government with an alliance spanning Israeli politics from far right to left, including .
is the new prime minister - for the next two years, under the coalition deal - but the ultra-Orthodox parties refused to join, fearing what they claim is a government that goes against "Jewish values."
Days before the new government was sworn in, Shas party head and ex-interior minister Arye Deri warned the new coalition would be "throwing in the garbage all the values the Jewish people sanctified for thousands of years".
Bennett, who defines himself as religious, responded sharply.
"Ultra-orthodox MPs won't teach us what Judaism is," Bennett said.
For ultra-Orthodox parties, a major concern will be waning state financial support, with many of their educational and social institutions "existing solely thanks to such funding," said Ilan Greilsammer, a political science professor at Bar Ilan University.
Many of the Haredim study in state subsidised religious institutions - called yeshivot - rather than work.
The ultra-Orthodox parties also face losing control of the powerful parliamentary finance committee, held for years by UTJ lawmakers, said Greilsammer.
The new finance minister is secular nationalist Avigdor Lieberman, who said recently that the ultra-Orthodox should, along with Netanyahu, be "put in a wheelbarrow and taken out to the dump."
Some fear that religious issues could be wrested from their hands, and controlled by representatives of Judaism's other streams.
Issues of state and religion are not prioritised in the new government's guidelines, where an ambiguous goal of "strengthening of the Jewish identity" appears.
'Parliamentary war'
To the ultra-Orthodox, the new prime minister, who dons a discreet skullcap to his head, is a "Reform" Jew - their worst insult.
"We are waging a parliamentary war against this coalition, which endangers the country's Jewish identity," said Yossi Taieb, a former Shas lawmaker and rabbi by training.
Taieb was particularly concerned that Bennett would push to end the military service exemption for religious students, allow public transport on the Sabbath, and ease the conversion process to Judaism.
Ultra-Orthodox lawmakers also fear the Bennett-Lapid government will change the historic status quo - in force since Israel's establishment in 1948 - where religious aspects of public life conform to ultra-Orthodox Judaism.
One of the first arguments between government and the ultra-Orthodox parties could concern an inquiry into , nearly all of them ultra-Orthodox.
Netanyahu's government did not appoint a commission of inquiry despite public pressure, after the ultra-Orthodox political leadership demanded to be in charge of any investigation.