Ali Moshref held aloft the Saudi flag with the Islamic profession of faith at a rally in the heart of Cairo in support of President Mohamed Morsi, whose sweeping new powers have put Islamists and their opponents at loggerheads.
Marches from different mosques across the city poured into Al-Nahda Square, where hundreds of thousands of Morsi supporters invoked the president's democratic election, yet simultaneously demanded the implementation of Islamic law.
A Salafist flag declared "Morsi: Egypt's elected president," while protesters chanted "The people want Sharia law implemented."
Saturday's Islamist rally rivaled in size the protests on Friday by mostly secular and liberal opponents of Morsi's perceived power grab and an Islamist panel's approval of a controversial draft constitution.
The Muslim Brotherhood said demonstrators from other Egyptian cities had arrived on buses to join the throng.
"We're for democracy," said Mohammed Fayed, a 37-year-old arts student at Cairo University, where the rallies converged. "And this man was voted for by the people in free and fair elections."
"The (secular) opposition say they support democracy, but now they're condemning it because Morsi came via the ballot box, and they're not happy about that," he added.
Businessman Ihab Fuad interjected. "I'm not a member of the Brotherhood, but I'm for Morsi. The majority of Egyptians support the Islamists. It's a fact."
Egypt's latest political crisis comes almost two years after the popular uprising that unseated Hosni Mubarak, when Islamist and secular opponents of the former dictator joined forces.
The current standoff has featured a strike by some of the country's top courts, many of whose judges remain from the Mubarak era. The courts are set to vote on the potential dissolution of the Islamist-run constituent assembly on Sunday.
Signup to our newsletter and follow us on Facebook and Twitter!
"This is a revolution that will not be aborted by Mubarak's judges," said trainee doctor Islam al-Baghdadi.
Earlier this year, the Supreme Constitutional Court disbanded parliament, dominated by the Islamists, on technical grounds.
"They dissolved the parliament that was elected by 30 million Egyptians, because the (election) laws were unconstitutional -- laws that they themselves created," Baghdadi added.
Supporters of the Morsi's Muslim Brotherhood quote the new constitution as fluidly as they do verses of the Koran, citing its articles that address religious freedom.
"We love all our countrymen, our Christian brothers and other religions," Baghdadi stressed.
But ultimately, calls to implement Islamic law appear to trump brotherly nationalist feeling.
Taxi driver Mohammed Saeed was adamant, arguing that the election of an Islamist president indicated that the majority wanted Islamic law.
"In Europe, as a Muslim minority, do we demand Sharia law? No. And here, we're a majority, so we want Sharia."
At first Moshref's flag seemed out of place among the countless Egyptian ones flying, but the slogans emanating from the packed-out square suggested it represented the goals of Saturday's Islamist protesters.
"Why the Saudi flag? Because it says 'There is no god but God, and Mohammed is the Prophet of God,'" said the 42-year-old Egyptian carpenter.
"National borders mean nothing to us. We are one ummah (Islamic nation). The Egyptian Muslim is the brother of the Saudi and the American muslim."