Abd al-Aziz ibn Baz
ISIS has been excommunicated from Islam by a number of scholars. Sheikh Muhammad al-Yaqoubi enumerated in his book, Refuting ISIS, that their form of Kharijism has removed them from Islam and fighting them is a religious duty, stating: "ISIS' leaders are people of unbelief and misguidance, and Muslims should not be lured by their jihad or deceived by their propaganda, as their actions speak louder than their words." Abd al-Aziz ibn Baz, the former Grand Mufti of Saudi Arabia, also stated that Kharijites are not Muslims, saying: "the majority are of the opinion that they are disobedient and misguided innovators, though they do not deem them unbelievers. However, the correct opinion is that they are unbelievers."