[6][7] The Quran, the central religious text of Islam, states in 4:48 that God will not forgive shirk if one dies without repenting of it.
[d] The word shirk comes from the Arabic root sh-r-k (ش ر ك), with the general meaning of 'to share'.
[15]: 41 [16]: 77 After Judgement Day, they will be cast into Hell along with devils (fallen angels) and evil jinn,[15]: 41 to whom the polytheists are said to sacrifice in order to gain protection.
Charles Adams writes that the Quran reproaches the People of the Book with kufr for rejecting Muhammad's message when they should have been the first to accept it as possessors of earlier revelations, and singles out Christians for disregarding the evidence of God's unity.
[22] Some Muslim thinkers such as Mohamed Talbi have viewed the most extreme Qur'anic presentations of the dogmas of the Trinity and divinity of Jesus (Al-Ma'idah 5:19, 5:75-76, 5:119)[18] as non-Christian formulas, which were rejected by the Church as well.
[25] In the Quran Jews and Christians, although accused of believing shared divinity by asserting lineage between God and Ezra or Jesus respectively, are not described as mushrik.
Nonetheless, medieval Muslim philosophers identified belief in the Trinity with shirk ("associationism"), by limiting the infinity of God by associating his divinity with physical existence.
One who keeps the fast, or gives alms, or performs the hajj to show the public his righteousness or to earn good name is a polytheist.Mahmud ibn Lubayd reported, Allah's messenger said: "The thing I fear for you the most is ash-Shirk al-Asghar."
"[40] According to Sufi teachings, to avoid "hidden shirk" (al-shirk al-khafi), it is necessary to focus solely on God and give up one's own will.
[42] Abdullah Ansari describes the highest stage of tawhid a human can possess, when the mind becomes fully immersed in the presence of God and understand how all things are put into their proper places.
[citation needed] Muhammad ibn Abd al-Wahhab, founder of the Wahhabi movement, classified shirk into three main categories.