Muslim scholars and movements from across the Sunni Islamic spectrum have rejected the caliphate declared by the Islamic State group, with the fighters receiving scathing criticism from both mainstream religious leaders, and those associated with their former allies, al-Qaeda.
Assem Barqawi, also known as Abu Mohamed al-Maqdesi, who was released from a Jordanian prison in June after serving a sentence for recruiting volunteers to fight in Afghanistan, called fighters loyal to the Islamic State group's leader, Abu Bakr al-Baghdadi, "deviant".
Maqdesi, a supporter of the al-Qaeda-affiliated Nusra Front, hit out at the Islamic State group for its brutal methods. "Is this caliphate a sanctuary for the vulnerable and a refuge for all Muslims, or a sword hanging over those Muslims who disagree with them," Maqdesi said.
In rejecting the self-proclaimed caliphate, Maqdesi, a Salafi, has found himself on the same side as Sufi leaders, such as the Syrian Muhammad al-Yacoubi.
In a post on his Twitter account, the Syrian exile similarly described the followers of the group, formerly known as the Islamic State in Iraq and the Levant (ISIL), as "deviators".
"[The] Khilafah state (ISIL) declared is illegitimate," Yacoubi said. Adding that supporting it is "haram", or forbidden.
The view was echoed by Qatar-based Egyptian religious leader, Yusuf al-Qaradawi, who said the declaration was "void" according to Islamic law.
"A group simply announcing a caliphate, is not enough to establish a caliphate," Qaradawi said in an open letter published on the website for the International Union of Muslim Scholars, which he heads.
There was similar admonishment from the pan-Islamic political party Hizb ut-Tahrir, which believes it is a religious obligation for Muslims to work towards establishing a caliphate.
"The issue of the Khilafah is too great for its image to be distorted or for its reality to be changed merely by an announcement here or an announcement there," the group said in a statement on its website.
Speaking during Friday prayers, Rachid Ghannouchi, the founder of the Ennahda Party, Tunisia's main Islamist party, added to the chorus of criticism, calling the declaration of a caliphate by followers of Baghdadi a "reckless" act, which gave a "deceptive message".
"Nations do not arise in this ridiculous way," he told his followers.
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Farid Senzai, a professor of Middle East politics at Santa Clara University, told Al Jazeera many Muslim groups felt the Islamic State group was hurting their cause.
"The Baghdadi caliphate is rejected by most mainstream Islamists because they feel it damages their cause to establish an Islamic system through peaceful means," Senzai said.
He added the fighters were further discredited by their "harsh implementation" of Islamic law.
According to Senzai, that rejection was shared among ordinary believers.
"Many Muslims would support a caliphate as an idea but not support ISIL because of its violent methodology," he said.
Despite its sizeable list of critics, the disapproval is unlikely to have a big effect on Baghdadi’s followers.
"They do not care about traditional and mainstream scholars, they have their own interpretation which they continue to insist gives them legitimacy," Senzai said.
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