Takfiri (, lit. "excommunicational") is an Arabic and Islamic term denoting a Muslim who excommunicates one of his/her coreligionists, i.e. who accuses another Muslim of being an apostate. Since according to the traditional interpretations of Islamic law (sharīʿa) the punishment for apostasy is the death penalty, and potentially a cause of strife and violence within the Muslim community (Ummah), an ill-founded accusation of takfīr is considered a major forbidden act (haram) in Islamic jurisprudence, with one ḥadīth declaring that one who wrongly declares another Muslim to be an unbeliever is himself an apostate. Takfirism has been called a "minority ideology" which "advocates the killing of other Muslims declared to be unbelievers". The accusation itself is called takfīr, derived from the Arabic word kāfir ("unbeliever"), and is described as when "one who is a Muslim is declared impure." An apostate is a murtad. In principle, in mainstream Sunnī Islam, the only group authorized to declare another Muslim a kāfir are the scholars of Islam (Ulama), and this is only done if all the prescribed legal precautions have been taken. An ill-founded accusation of takfīr is a major forbidden act (haram) in Islamic jurisprudence. Traditionally, the declaration of takfīr was used against self-professed Muslims who denied one or more of the basic tenets of Islam. Throughout the history of Islam, Islamic denominations and movements such as Shīʿa Muslims and the Ahmadiyya Muslim Community have been accused of takfīr and labeled as kuffār ("unbelievers") by Sunnī Muslims, becoming victims of religious discrimination, violence, and persecution perpetrated against them over the centuries. In the history of Islam, a sect originating in the 7th century CE known as the Kharijites carried out takfīr against both Sunnī and Shīʿa Muslims, and became the main source of insurrection against the early caliphates for centuries. Since the latter half of the 20th century, takfīr has also been used for "sanctioning violence against leaders of Islamic states" who do not enforce sharia or are otherwise "deemed insufficiently religious". This arbitrary application of takfīr has become a "central ideology" of insurgent Wahhabi-Salafi jihadist extremist and terrorist groups, particularly al-Qaeda and ISIL/ISIS/IS/Daesh, who have drawn on the ideas of the medieval Islamic scholars Ibn Taymiyyah and Ibn Kathir, and those of the modern Islamist ideologues Sayyid Qutb and Abul A'la Maududi. The practice of takfīr has been denounced as deviant by the mainstream branches of Islam and mainstream Muslim scholars such