[12] Muslims believe that Islam is the complete and universal version of a primordial faith that was revealed many times through earlier prophets and messengers, including Adam, Noah, Abraham, Moses, and Jesus.

The Five Pillars, considered obligatory acts of worship, are the Islamic oath and creed (shahada), daily prayers (salah), almsgiving (zakat), fasting (sawm) in the month of Ramadan, and a pilgrimage (hajj) to Mecca.

The expansion of the Muslim world involved various states and caliphates as well as extensive trade and religious conversion as a result of Islamic missionary activities (dawah), as well as through conquests, imperialism, and colonialism.

[73][74][75] On Yawm al-Qiyāmah, Muslims believe all humankind will be judged by their good and bad deeds and consigned to Jannah (paradise) or Jahannam (hell).

[iv] The concept of divine predestination in Islam (Arabic: القضاء والقدر, al-qadāʾ wa l-qadar) means that every matter, good or bad, is believed to have been decreed by God.

[81][82][83][84] Muslims often express this belief in divine destiny with the phrase "In-sha-Allah" (Arabic: إن شاء الله) meaning "if God wills" when speaking on future events.

[85] There are five acts of worship that are considered duties–the Shahada (declaration of faith), the five daily prayers, Zakat (almsgiving), fasting during Ramadan, and the Hajj pilgrimage–collectively known as "The Pillars of Islam" (Arkān al-Islām).

[112] All Muslim men wear only two simple white unstitched pieces of cloth called ihram, intended to bring continuity through generations and uniformity among pilgrims despite class or origin.

[126] The Meccan elite felt Muhammad was destabilizing their social order by preaching about one God and giving questionable ideas to the poor and slaves because they profited from the pilgrimages to the idols of the Kaaba.

[136][137][138][139][140] Local populations of Jews and indigenous Christians, persecuted as religious minorities and heretics and taxed heavily, often helped Muslims take over their lands,[141] resulting in rapid expansion of the caliphate into the Persian and Byzantine empires.

Some Muslims began questioning the piety of indulgence in worldly life and emphasized poverty, humility, and avoidance of sin based on renunciation of bodily desires.

[165][b] Greek rationalist philosophy influenced a speculative school of thought known as Muʿtazila, who famously advocated the notion of free-will originated by Wasil ibn Ata.

Philosophers such as Al-Farabi, Avicenna and Averroes sought to harmonize Aristotle's ideas with the teachings of Islam, similar to later scholasticism within Christianity in Europe and Maimonides' work within Judaism, while others like Al-Ghazali argued against such syncretism and ultimately prevailed.

[172][173][174][175][143] Islamic scientific achievements spanned a wide range of subject areas including medicine, mathematics, astronomy, and agriculture as well as physics, economics, engineering and optics.

[227] Earlier in the 14th century, Ibn Taymiyya promoted a puritanical form of Islam,[228] rejecting philosophical approaches in favour of simpler theology,[228] and called to open the gates of itjihad rather than blind imitation of scholars.

[265] In opposition to Islamic political movements, in 20th century Turkey, the military carried out coups to oust Islamist governments, and headscarves were legally restricted, as also happened in Tunisia.

[280] Among other groups, this access to information has led to the rise of popular "televangelist" preachers, such as Amr Khaled, who compete with the traditional ulema in their reach and have decentralized religious authority.

[281][282] More "individualized" interpretations of Islam[283] notably involve Liberal Muslims who attempt to align religious traditions with contemporary secular governance,[284][285] an approach that has been criticized by some regarding its compatibility.

[328] Sunnis, or sometimes Sunnites, believe that the first four caliphs were the rightful successors to Muhammad and primarily reference six major hadith works for legal matters, while following one of the four traditional schools of jurisprudence: Hanafi, Hanbali, Maliki or Shafi'i.

Maturidism, founded by Abu Mansur al-Maturidi (853–944 CE), asserts that scripture is not needed for basic ethics and that good and evil can be understood by reason alone,[332] but people rely on revelation, for matters beyond human's comprehension.

Ash'arism, founded by Al-Ashʿarī (c. 874–936), holds that ethics can derive just from divine revelation but accepts reason regarding exegetical matters and combines Muʿtazila approaches with traditionalist ideas.

[346] Shias state the community deliberately ignored Ali's nomination,[347] citing Umar's appointment by Abu Bakr,[348] other historical evidence,[349] and the Qur'an's stance that majority does not imply legitimacy.

Classical Sufi scholars defined tasawwuf as "a science whose objective is the reparation of the heart and turning it away from all else but God", through "intuitive and emotional faculties" that one must be trained to use.

[393] Traditional Sufis, such as Bayazid Bastami, Jalaluddin Rumi, Haji Bektash Veli, Junaid Baghdadi, and Al-Ghazali, argued for Sufism as being based upon the tenets of Islam and the teachings of the prophet.

Rulings assign actions to one of five categories called ahkam: mandatory (fard), recommended (mustahabb), permitted (mubah), abhorred (makruh), and prohibited (haram).

[427] Jihad means "to strive or struggle [in the way of God]" and, in its broadest sense, is "exerting one's utmost power, efforts, endeavors, or ability in contending with an object of disapprobation".

[428][429] Jihad is the only form of warfare permissible in Islamic law and may be declared against illegal works, terrorists, criminal groups, rebels, apostates, and leaders or states who oppress Muslims.

[481] The Druze faith further split from Isma'ilism as it developed its own unique doctrines, and finally separated from both Ismāʿīlīsm and Islam altogether; these include the belief that the Imam Al-Ḥākim bi-Amr Allāh was God incarnate.

[484] Bábism stems from Twelver Shia passed through Siyyid 'Ali Muhammad i-Shirazi al-Bab while one of his followers Mirza Husayn 'Ali Nuri Baha'u'llah founded the Baháʼí Faith.

Ali ibn Sahl Rabban al-Tabari defended the Quranic description of paradise by asserting that the Bible also implies such ideas, such as drinking wine in heaven in the Gospel of Matthew.