ISIL Ideology and Beliefs

 ISIL is a Salafi group.  It follows an extreme interpretation of Islam, promotes religious violence, and regards those who do not agree with its interpretations as infidels or apostates.  ISIL has demonstrated that ideology and adherence to Islamic beliefs and laws are secondary to its criminal financial enterprises supporting the group's activities.  According to Hayder al Khoei, ISIL's philosophy is represented by the symbolism in the Black Standard variant of the legendary battle flag of Muhammad that it has adopted: the flag shows the Seal of Muhmmad within a white circle, with the phrase above it, "There is no God but Allah".Such symbolism has been said to point to ISIL's belief that it represents the restoration of the caliphate of early Islam, with all the political, religious and eschatological ramifications that this would imply.  Saudi Arabia was criticised by Noam Chomsky in October 2014 of having "long been the major source of funding for ISIS as well as providing its ideological roots" (i.e. Salafism or Wahhabism).  According to Owen Jones at The Guardian, "Salafists across the Middle East receive ideological and material backing from within the kingdom" of Saudi Arabia, and America knows this, with Hillary Clinton having called Saudi donors "the most significant source of funding to Sunni terrorist groups worldwide".  Some people in Saudi Arabia applaud ISIL for fighting Iranian Shi’ite "fire" with Sunni "fire".

According to some observers, ISIL emerged from the ideology of the Muslim Brotherhood, the first post-Ottoman Islamist group dating back to the late 1920s in Egypt.  It adheres to global jihadist principles and follows the hard-line ideology of al-Qaeda and many other modern-day jihadist groups.

However, other sources trace the group's roots not to the Islamism of the Muslim Brotherhood and the more mainstream jihadism of al-Qaeda, but to Wahhabism. The New York Times wrote:

For their guiding principles, the leaders of the Islamic State ... are open and clear about their almost exclusive commitment to the Wahhabi movement of Sunni Islam. The group circulates images of Wahhabi religious textbooks from Saudi Arabia in the schools it controls. Videos from the group’s territory have shown Wahhabi texts plastered on the sides of an official missionary van.

ISIL aims to return to the early days of Islam, rejecting all innovations in the religion, which it believes corrupts its original spirit. It condemns later caliphates and the Ottoman Empire for deviating from what it calls pure Islam, and seeks to revive the original Wahhabi project of the restoration of the caliphate governed by strict Salafist doctrine. Following Salafi-Wahhabi tradition, ISIL condemns the followers of secular law as disbelievers, putting the current Saudi government in that category.

Salafists such as ISIL believe that only a legitimate authority can undertake the leadership of jihad, and that the first priority over other areas of combat, such as fighting non-Muslim countries, is the purification of Islamic society. For example, ISIL regards the Palestinian Sunni group Hamas as apostates who have no legitimate authority to lead jihad and it regards fighting Hamas as the first step toward confrontation with Israel.

Eschatology

One difference between ISIL and other Islamist and jihadist movements is its emphasis on eschatology and apocalypticism, and its belief that the arrival of the Mahdi is imminent. ISIL believes it will defeat the army of "Rome" at the town of Dabiq in fulfilment of prophecy.

Theological objections

According to The New York Times, "All of the most influential jihadist theorists are criticizing the Islamic State as deviant, calling its self-proclaimed caliphate null and void" and have denounced it for its beheading of journalists and aid workers.  ISIL is widely denounced by a broad range of Islamic clerics, including al-Qaeda-oriented and Saudi clerics.

Sunni critics, including Salafi and jihadist muftis such as Adnan al-Aroor and Abu Basir al-Tartusi, say that ISIL and related terrorist groups are not Sunnis, but modern-day Khawarij—Muslims who have stepped outside the mainstream of Islam—serving an imperial anti-Islamic agenda.  Other critics of ISIL's brand of Sunni Islam include Salafists who previously publicly supported jihadist groups such as al-Qaeda, for example the Saudi government official Saleh Al-Fawzan, known for his extremist views, who claims that ISIL is a creation of "Zionists, Crusaders and Safavids", and the Jordanian-Palestinian writer Abu Muhammad al-Maqdisi, the former spiritual mentor to Abu Musab al-Zarqawi, who was released from prison in Jordan in June 2014 and accuses ISIL of driving a wedge between Muslims.

http://en.wikipedia.org/wiki/Islamic_State_of_Iraq_and_the_Levant