“Public transportation is a necessity: I think it should be like electricity or water or gas,” said Omry Hazut, 27, who started the Facebook protest. “State and religion, this bond, is broken a lot of times, but only if you can afford it. If you can afford a car, you can pull the switch and start it on Saturday, but if you can’t, you won’t have any option of leaving your house.”

As Prime Minister Benjamin Netanyahu tries to stitch together a new governing coalition that is expected to be made up of rightist and religious parties, a continuing struggle over Israeli identity is in the balance. The debate over transportation is part of a larger one over a so-called nationality bill that seeks to redefine the relationship between Israeli democracy and Jewish character, which was among the divisive issues that helped collapse Mr. Netanyahu’s previous coalition last fall.

Controversy over public transportation predates Israel’s establishment in 1948 — Tel Aviv once banned horse-drawn carriages from its main street on Saturdays — but recent efforts to change the status quo, in which buses are idle in all but a few places, have met stiff opposition.

Now, a cooperative is starting minibus service in Jerusalem on May 1, financed by a crowd-funded $30,000. Mr. Hazut plans a new Facebook movement for Shavuot, when buses will be stilled for two days at the end of May. Environmentalists and those concerned about economic disparities have embraced the cause.

Orthodox Jews do not use motor vehicles on the Sabbath and holidays because of prohibitions on igniting fuel, creating sparks and traveling beyond certain distances. Though adherents to these strictures make up perhaps a fifth of Israel’s population, others who themselves drive see the bus ban as an important way of distinguishing the Jewish state.