But even some of their closest supporters said they would believe it when they saw it.
About 700 members of the Gathering of Islamic Students of Iraq packed the auditorium of a hotel and listened to Shia politicians and clerics predict a bright future once Iraq's new constitution was drafted and approved.
Vice-President Adel Abdul Mahdi said everyone's rights would be guaranteed by the constitution.
"This is a new era for the people. The constitution will not hurt the rights of any individuals. We are building, we will be united. The constitution will guarantee everyone's rights."
Iraq's new leaders, who won January elections that sidelined Sunnis once dominant under Saddam Hussein, are hoping the charter will defuse the fighting.
Vehicle for stability
The document is also a cornerstone of US policy and is seen as a vehicle for stabilising the country.
"We have lived under a dictatorship for 35 years. Saddam was the only constitution. It's one thing to talk about the constitution but it is how you implement that counts," said Sattar Hasim, 21.
"Iraqis are the type of people who will get violent if we don't have all our rights," he added.
The constitution drafting committee, which will decide on Monday whether they need a six-month extension to finish the document, faces a complex minefield over issues such as the role of religion in the state, and federalism.
Arab Sunnis are afraid the granting of autonomy, which the Kurds already enjoy in the north, would split the country, especially at a time of growing tensions.
But Sunnis are not the only Iraqis opposed to federalism.
"We don't want federalism, it will tear apart the country," said theatre student Ahmad Hasan, 28. "I admire our leaders but I will be convinced of the constitution only when I see it."
"We don't want federalism, it will tear apart the country. I admire our leaders but I will be convinced of the constitution only when I see it"
Others were optimistic.
Iraqi leaders say Islam will be the main source for law but each sect will enjoy equal rights.
"It all depends on what the clerics try to do. It is one thing to say Islam is the state religion and another to interfere," said Ibrahim.
Meanwhile, the fighting that Shia leaders hope the constitution will halt continued on Thursday as Iraqi army checkpoints northeast of Baghdad came under fire, leaving four Iraqi soldiers dead.
Fighting broke out at about 2.30pm along the road between Baquba, 55km northeast of Baghdad, and Khan Dhari, police Colonel Mudhaffar Muhammad said.
Police were fired upon with automatic weapons and rocket-propelled grenades during the attacks, he added.