Ronen Bar, the chief of Israel’s domestic security agency Shin Bet, said that Prime Minister Benjamin Netanyahu had repeatedly pressed him to overstep his agency’s legal boundaries by essentially spying on citizens leading anti-government protests and on the protest movement’s funders, according to an affidavit published on Monday.

But perhaps more astonishingly, Mr. Bar said that Mr. Netanyahu demanded that he be loyal to him rather than follow Supreme Court rulings in the event of a constitutional crisis.

These and other stunning allegations appeared in a written, public affidavit that Mr. Bar submitted to the Supreme Court on Monday as part of a case brought by Israeli watchdog organizations and opposition parties against Mr. Netanyahu’s attempt to fire his domestic security chief.

Mr. Bar said that Mr. Netanyahu’s desire to dismiss him had coincided with his decision to investigate Netanyahu aides suspected of security breaches in cases involving the leaking of classified documents and ties to Qatar.

The scathing affidavit laid bare the depths of a domestic crisis that pits Mr. Netanyahu’s ultranationalist and religiously conservative ruling coalition against more liberal Israelis over the balance of power between branches of government and the nature and future of Israeli democracy.

Mr. Netanyahu tried to fire Mr. Bar last month, citing a lack of trust between them. Mr. Bar wrote that he did not know all the reasons behind Mr. Netanyahu’s desire to terminate his services but that he had concluded that they did not stem from professional considerations, “but from an expectation of personal loyalty on my part toward the prime minister.”