Principle Six: The Qur’an’s Method of Establishing tawḥīd (monotheism) and Rejecting its Opposite
The whole of the Qur’an aims to affirm tawḥīd and negate whatever contradicts it. In most of its verses Allah confirms the oneness of His divinity and commands that all worship be devoted to Him alone, without partner. He tells us that every messenger was sent only to call his people to worship Allah and never associate anything with Him; that He created the jinn and humankind for no other purpose than that they worship Him; and that the scriptures, the messengers—even sound human nature and right reason—are unanimous upon this foundation, the foundation of all foundations. Whoever refuses to embrace this religion—sincere devotion in worship, heart, and deed to Allah alone—will have his works rendered null: “If you should associate others with Him, your deeds would surely be nullified” (al-Zumar 39:65); “Had they associated others with Him, all they used to do would have come to nothing” (al-Anʿām 6:88). The Qur’an calls the servants back to what their inborn nature and their intellects already acknowledge: that the One who alone creates and governs, who alone bestows every outward and inward blessing, is the only One worthy of worship; that no part of worship should be directed to anyone else; and that the rest of creation has no power to create, to confer benefit, or to avert harm from themselves, let alone to provide anything for others independently of Allah.

It also summons them to this foundation by the way Allah praises Himself and extols His noble Self—highlighting His exclusive possession of the attributes of greatness, glory, majesty, and perfection. The One endowed with this absolute, unparalleled perfection deserves that all outward and inward deeds be devoted purely to Him.

The Qur’an further establishes this tawḥīd by declaring that He alone is the Judge; no one else may legislate or impose reward and punishment: “Judgment belongs to none but Allah. He has commanded that you worship none but Him” (Yūsuf 12:40).

At other times it affirms the matter by mentioning the virtues of tawḥīd— the only religion that revelation, reason, and innate disposition make obligatory upon every servant—while exposing the evils and ugliness of shirk (polytheism) and the derangement of minds that it produces.