In Islam, blasphemy is impious utterance or action concerning God, but is broader than in normal English usage, including not only the mocking or vilifying of attributes of Islam but denying any of the fundamental beliefs of the religion. Examples include denying that the Quran was divinely revealed, the Prophethood of one of the Islamic prophets,Lorenz Langer (2014) Religious Offence and Human Rights: The Implications of Defamation of Religions Cambridge University Press p. 332 insulting an angel, or maintaining God had a son.

The Quran curses those who commit blasphemy and promises blasphemers humiliation in the Hereafter.Siraj Khan. "Blasphemy against the Prophet" , in Muhammad in History, Thought, and Culture (editors: Coeli Fitzpatrick and Adam Hani Walker). , pp. 59–61. However, whether any Quranic verses prescribe worldly punishments is debated: some Muslims believe that no worldly punishment is prescribed while others disagree.Siraj Khan. "Blasphemy against the Prophet" , in Muhammad in History, Thought, and Culture (editors: Coeli Fitzpatrick and Adam Hani Walker). , pp. 59–67. The interpretation of hadiths, which are another source of Sharia, is similarly debated. Some have interpreted hadith as prescribing punishments for blasphemy, which may include death, while others argue that the death penalty applies only to cases where perpetrator commits treasonous crimes, especially during times of war. Different traditional schools of jurisprudence prescribe different punishment for blasphemy, depending on whether the blasphemer is Muslim or non-Muslim, a man or a woman.

In the modern Muslim world, the laws pertaining to blasphemy vary by country, and some countries prescribe punishments consisting of fines, imprisonment, flogging, hanging, or beheading.P Smith (2003). "Speak No Evil: Apostasy, Blasphemy and Heresy in Malaysian Syariah Law". UC Davis Journal Int'l Law & Policy. 10, pp. 357–73. N Swazo (2014). "The Case of Hamza Kashgari: Examining Apostasy, Heresy, and Blasphemy Under Sharia". The Review of Faith & International Affairs 12(4). pp. 16–26. Capital punishment for blasphemy was rare in pre-modern Islamic societies. In the modern era some states and radical groups have used charges of blasphemy in an effort to burnish their religious credentials and gain popular support at the expense of liberal Muslim intellectuals and religious minorities. Other Muslims instead push for greater freedom of expression. Contemporary accusations of blasphemy against Islam have sparked international controversies and incited mob violence and assassinations.

Islamic scripture In Islamic literature, blasphemy is of many types, and there are many different words for it: (insult) and (abuse, vilification), or (denial), (concoction), or (curse) and (accuse, defame).See: Siraj Khan. "Blasphemy against the Prophet", in Muhammad in History, Thought, and Culture (ed: Coeli Fitzpatrick Ph.D., Adam Hani Walker). , pp. 59–67. Hassner, R. E. (2011). "Blasphemy and Violence". International Studies Quarterly 55(1). pp. 23–24; Lewis, Bernard. "Behind the Rushdie affair." The American Scholar 60.2 (1991), pp. 185–96; Stanfield-Johnson, R. (2004). "The tabarra'iyan and the early Safavids". Iranian Studies 37(1). pp. 47–71. In Islamic literature, the term "blasphemy" sometimes also overlaps with ("unbelief"), (depravity), (insult), and (apostasy).Talal Asad, in Hent de Vries (ed.). Religion: Beyond a Concept. Fordham University Press (2008). . pp. 589–92

Quran

A number of verses in the Qur'an have been interpreted as relating to blasphemy. In these verses God admonishes those who commit blasphemy. Some verses are cited as evidence that the Qur'an does not prescribe punishments for blasphemy, while other verses are cited as evidence that it does.

The only verse that directly says blasphemy (sabb) is Q6:108. The verse calls on Muslims to not blaspheme against deities of other religions, lest people of that religion retaliate by blaspheming against Allah.

Verse 5:33 prescribes prison or mutilation or death for those "who wage war against Allah and His Messenger". Even though the verse doesn't mention blasphemy (sabb), some commentators have used to justify punishments for blasphemy.According to Abbas "waging war against Allah and His messenger" must be interpreted as "those who disbelieve in Allah and His messenger", according to the two Jalals the verse is directed towards who "fights against Muslims", according to Kathir "waging war" "includes disbelief". See Other commentators believe this verse only applies to those who commit crimes against human life and property.

33:57–61 have also been used by some commentators to justify blasphemy punishments.Brian Winston (2014). The Rushdie Fatwa and After: A Lesson to the Circumspect, Palgrave Macmillan. . p. 74, Quote: "(In the case of blasphemy and Salman Rushdie) the death sentence it pronounced was grounded in a jurisprudential gloss on the Surah al-Ahzab (33:57)".Richard T. Antoun (2014). Muslim Preacher in the Modern World. Princeton University Press. . p. 194, Quote: "All the negative connotations of factionalism, social dissension, blasphemy, and their logical conclusions conspiracy, military confrontation and damnation – are captured in the title of this sura, al-Ahzab (The Confederates, Book 33)" However, other scholars opined that verses 33:57–61 could only have been acted upon during the life of the Prophet and since the demise of Muhammad they are no longer applicable.

Other passages are not related to any earthly punishment for blasphemy, but prescribe Muslims to not "sit with" those who mock the religionAccording to Akyol, this verse indicates that "Muslims are not supposed to be part of a discourse that mocks Islam, but all they have to do is stay away from it. Even then, the withdrawal should last only until the discourse changes into something inoffensive. Once mockery ends, dialogue can restart". See Akyol, Mustafa, Islam Without Extremes: A Muslim Case for Liberty, 2013 p. 285 – although the latter are admonishments directed towards a witness of blasphemy rather than the guilty of blasphemy:

According to Shemeem Burney Abbas, the Qur'an mentions many examples of disbelievers ridiculing and mocking Muhammad, but never commands him to punish those who mocked him. Instead, the Qur'an asks Muhammad to leave the punishment of blasphemy to God, and that there would be justice in the afterlife.

Hadith According to several hadiths, Muhammad ordered a number of enemies executed "in the hours after Mecca's fall". One of those who was killed was Ka'b ibn al-Ashraf, because he had insulted Muhammad.Rubin, Uri. The Assassination of Kaʿb b. al-Ashraf. Oriens, Vol. 32. (1990), pp. 65–71.

A variety of punishments, including death, have been instituted in Islamic jurisprudence that draw their sources from hadith literature. Sources in hadith literature allege that Muhammad ordered the execution of Ka'b ibn al-Ashraf. After the Battle of Badr, Ka'b had incited the Quraysh against Muhammad, and also urged them to seek vengeance against Muslims. Another person executed was Abu Rafi', who had actively propagandized against Muslims immediately before the Battle of Ahzab. Both of these men were guilty of insulting Muhammad, and both were guilty of inciting violence. While some have explained that these two men were executed for blaspheming against Muhammad, an alternative explanation is that they were executed for treason and causing disorder (fasad) in society.

Muhammad declared that there shall be no punishment for murdering anyone who disparages, abuses or insults him (, ). One hadith tells of a man who killed his pregnant slave because she persisted in insulting Muhammad. Upon hearing this, Muhammad is reported to have exclaimed: "Do you not bear witness that her blood is futile!" () This expression can be read as meaning that the killing was unnecessary, implying that Muhammad condemned it. However, most hadith specialists interpreted it as voiding the obligation of paying the blood money which would normally be due to the woman's next of kin. Another hadith reports Muhammad using an expression which clearly indicates the latter meaning:

Some jurists suggest that the sunnah in and provide a basis for a death sentence for the crime of blasphemy, even if someone claims not to be an apostate, but has committed the crime of blasphemy. Some modern Muslim scholars contest that Islam supports blasphemy law, stating that Muslim jurists made the offense part of Sharia.Islamic scholar attacks Pakistan's blasphemy laws Guardian 20 January 2010. Retrieved 23 January 2010

The words of Ibn Abbas, a prominent jurist and companion of Muhammad, are frequently cited to justify the death penalty as punishment blasphemy:

In Islamic jurisprudence, Kitab al Hudud and Taz'ir cover punishment for blasphemous acts.Peters, R. (2005). Crime and punishment in Islamic Law: Theory and practice from the Sixteenth to the Twenty-First Century (Vol. 2). Cambridge University Press.

Islamic law

Islamic jurisprudence The Quran curses those who commit blasphemy and promises blasphemers humiliation in the Afterlife. However, whether any Quranic verses prescribe worldly punishments is debated: some Muslims believe that no worldly punishment is prescribed while others disagree. Islamic jurisprudence (fiqh) of Sunni and Shia madhabs have declared different punishments for the religious crime of blasphemy, and they vary between schools. These are as follows:Saeed, Abdullah. "Ambiguities of Apostasy and The Repression of Muslim Dissent." The Review of Faith & International Affairs 9.2 (2011): 31–38.

Hanafi school In the Hanafi school, blasphemy is regarded as synonymous with apostasy, and therefore, accepts the repentance of apostates. Those who refuse to repent, their punishment is death if the blasphemer is a Muslim man, and if the blasphemer is a woman, she must be imprisoned with coercion (beating) till she repents and returns to Islam.*Abu al-Layth al-Samarqandi (983), Mukhtalaf al-Riwayah, vol. 3, pp. 1298–99 Ahmad ibn Muhammad al-Tahawi (933), Mukhtasar Ikhtilaf al-Ulama, vol. 3, p. 504 Ali ibn Hassan al-Sughdi (798); Kitab al-Kharaj; Quote: "أيما رجل مسلم سب رَسُوْل اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ أو كذبه أو عابه أوتنقصه فقد كفر بالله وبانت منه زوجته ، فإن تاب وإلا قتل ، وكذلك المرأة ، إلا أن أبا حنيفة قَالَ: لا تقتل المرأة وتجبر عَلَى الإسلام"; Translation: "A Muslim man who blasphemes the Messenger of Allah, denies him, reproaches him, or diminishes him, he has committed apostasy in Allah, and his wife is separated from him. He must repent, or else is killed. And this is the same for the woman, except Abu Hanifa said: Do not kill the woman, but coerce her back to Islam".