Clashes erupted again just before midnight, when el-Mahalawi told protesters outside the mosque that if they don’t disperse, his supporters will come free him. Minutes later, rocks were thrown at the protesters, and gunfire crackled in the distance. An Associated Press reporter on the scene saw at least four people injured from rock-throwing.
Clashes also broke out in the town of Nagaa Hammadi, 460 kilometers (290 miles) south of Cairo.
Sheik Osama el-Hawi, also a Salafi, told worshippers that approval of the constitution was the only way to restore stability after nearly two years of turmoil following the revolution that ousted Mubarak.
‘‘Saturday will be the day of victory for Shariah (Islamic law),’’ he said. His followers then briefly fought with protesters marching outside the mosque.
For many, the message in support of the constitution was a simple one: A ‘‘Yes’’ to the constitution is a yes to Islam.
Sheik Mohammed Sayyed, affiliated with the Muslim Brotherhood, put it bluntly during prayers at the el-Helali mosque elsewhere in Assiut. ‘‘Tomorrow is the day we will seek the victory of Islam,’’ he said.
‘‘The first phase of implementing Shariah (Islamic law) is the election of a Muslim president. The second phase is to hold a referendum on the constitution,’’ he said, urging voters to go to the polls in groups. ‘‘Those calling themselves liberals and the salvation of Egypt are saboteurs who sabotage Egypt.’’
In the southern city of Assuit, Sheik Abdel-Akher Hamad also urged worshippers to vote ‘‘yes.’’
‘‘Voting yes is like jihad for the sake of God,’’ he said during his sermon. ‘‘It preserves Egypt from evils and from those who want to sabotage Islam and Muslims.’’
Most of Egypt’s judges are refusing to monitor the vote, according to the powerful judges’ union, although authorities said they would be able to meet the legal obligation to have a judge at each polling station. There are more than 6,000 polling stations in 10 provinces, including Cairo and Alexandria, in the first round on Saturday.
‘‘Polling stations can’t open their doors unless there is a judge there,’’ Zaghloul el-Blashi, the head of the referendum committee, told the pan-Arab TV station Al-Jazeera.
The Carter Center, the international group founded by former U.S. President Jimmy Carter that has been monitoring Egyptian voting since last year’s uprising, said it would not deploy monitors for the referendum because of the government’s late release of monitoring regulations.
The crisis began when Morsi issued a decree on Nov. 22 giving himself and the assembly writing the draft immunity from judicial oversight so the document could be finalized before an expected court ruling dissolving the panel.
On Nov.30, the densely written document was then passed by an 85-member assembly mostly composed of Islamists in a marathon session despite a walkout by secular activists and Christians. Morsi then rushed it to a nationwide vote scheduled for the next two Saturdays.
If the constitution is approved by a simple majority of voters, the Islamists would gain even more power. The current upper house of parliament, dominated by Islamists, would be given the authority to legislate until a new parliament is elected.
If the constitution is defeated, elections would be held within three months for a new panel to write a new constitution. In the meantime, legislative powers would remain with Morsi.
Morsi, who took office in June after a narrow victory in the country’s first free elections, joined Friday prayers at the el-Farouk mosque near his house in eastern Cairo and left without giving a speech.
At least publicly, the cleric at his mosque remained neutral.
‘‘Those who think that rejecting or approving the constitution is the path to heaven or hell is mistaken,’’ he said, referring to a slogan used by some supporters of the draft constitution. ‘‘No one rules whether someone goes to heaven or hell but God almighty.’’