Jahmiyya

Jahmiyya was a term used by Islamic scholars to refer to the followers of the doctrines of Jahm bin Safwan (d. 128/746). Jahm and those associated with his school of thought appear as prominent heretics in Sunni heresiography, and to be called one of the Jahmiyya came to be used as an insult or polemic between some Sunni scholars. The Jahmiyya particularly came to be remembered for advocating for the denial or negation of God's divine attributes (known as the doctrine of taʿṭīl).

The views of Jahm and his followers are rejected in all surviving sources and across the spectrum of views in medieval Muslim theology, from the Hanbalites to the Mutazilites. At the same time, Jahm was also widely acknowledged as the figure who introduced the principle of intellect (ʿaql) into Islamic theological discourse, and the use of reasoning to derive opinions from propositions (raʾy).

Main figures
The eponymous figure behind the Jahmiyya was Jahm ibn Safwan. Jahm was born in Samarkand. He lived and taught in northeastern Iran and it is possibly that he never left the region of Greater Khorasan. The second figure most commonly associated with the Jami was the Kufan Ḍirār ibn ʻAmr. However, despite his association with the Jahmiyya, he may have never met Jahm and even criticized him in one of his works. No writings from either authors have survived, and information about their views relies on short summaries produced by other authors, primarily their opponents.

Another famous preacher of Jahmitic views was Bishr al-Marisi (d. 833). At the beginning of the 9th century, Jahmites acted in Nehavend, but some of them were forced to accept the teachings of the Asharites.

Beliefs
Jahm's basic physics and ontology were predicated on his distinction between the existent corporeal and incorporeal. The incorporeal refers to something that is non-body, or is non-existent. God, along with agency and causality, is among the existent incorporeal. According to Jahm, God, who is uncaused and necessarily exists, is the only immaterial existent and immaterial cause. Furthermore, composite immaterial things do not exist. Jahm and the Jahmiyya also argued that God was not a 'thing'; this was not to say that God did not exist but instead that God cannot be logically predicated on anything else or be described by a reference to a set of properties.

The Jahmiyya also accepted the notion of the negation of divine attributes (ta'til), which, alongside antianthropormophism (tanzih), is a view that reacts or responds to anthropomorphism (tashbih) and its advocates who attempt to understand God, including the attributes of God, by comparing God to the attributes of that which God created. However, the Jahmiyya believed that God was incomparable to anything in the cosmos, and so people should avoid ascribing any properties or qualities to God since this was beyond human knowledge. Such claims, in fact, constitute innovation in religious matters (bid'ah) and so should be rejected.

Some heresiographers also described the Jahmiyya as extreme Jabriyya, meaning that they believed in predestination and rejected human free will. The Jahmiyya believed this because they thought that human free will would entail a limitation on God's power, and so must be rejected.

Criticism
Since the advent of Jahmism, this tendency has been the subject of criticism by many prominent representatives of Sunni Islam. Some of the most prominent critics included Ahmad ibn Hanbal, Ibn Qutayba, Ibn Qayyim al-Jawziyya, Abu Hamid al-Ghazali, Ibn Hajar al-Asqalani and Ibn Taymiyyah. Yasir Qadhi wrote a lengthy dissertation (in Arabic) entitled "The Theological Opinions of Jahm b. Ṣafwān and Their Effects on the Other Islamic Sects." Ibn Taymiyyah criticized Kalām as having adopted doctrines of Jahmism and instead advocated for a theology based on his the idea of a return to the time of Muhammad's salafs.

Ibn al-Mubarak criticized the Jahmiyya rejection of free will in his poetry. In particular, he argued that this rejection would imply that evil figures could not be blamed for the actions that they performed. Therefore, the actions of Pharaoh and Haman could not really be imputed onto them. Not only this, but their moral character and actions would have to be placed alongside figures such as Moses, since all of their actions have been predetermined. In some famous lines of his poetry, Ibn al-Mubarak derived the name Jahmiyya from the word jahannam (hell). His anti-Jahmite poetry was cited by al-Bukhari.

Derogatory term
The label "Jahmiyya" came to be used as an insult due to its negative connotations. For example, Abu Hanifa and Muhammad al-Shaybani were labelled as a 'Jahmi' by some Sunni scholars. Ibn Taymiyya used it to describe the Ash'ari mutakallimūn (a scholar of kalam) of his time. In later periods, Wahhabis also adopted the term as a derogatory reference to practitioners of kalam theology, in order to argue that they, like Jahm, denied God's attributes. In particular, this accusation was levelled by early Wahhabis against Maliki Muslims living in eastern Arabia (sometimes singled out as being located in Dubai and Abu Dhabi), who they believed to interpret the attributes of God in a purely metaphorical sense.