Tawhid means “unification” (making something one) or “asserting oneness,” and it comes from the Arabic verb wahhada which itself means to unite, unify, or consolidate. However, when the term Tawhid is used in reference to Allah Tawhidullah, it means realizing and maintaining of Allah’s unity in all of mans actions which directly or indirectly relate to Him. It is the belief that Allah is One, without partner in His dominion (Rububiyah), One without similitude in His essence and sttributes (Asma’ was-Sifat), and One without rival in His divinity and in worship (Uluhiyah / Ibadah). These three aspects from the basis for the categories into which the science of Tawhid has been traditionally divided.
The three categories of Tawhid are commonly referred to by the following titles:
a) Tawhid ar-Rububiyah (lit. Maintaining the unity of Lordship”) that is, affirming that Allah is one, without partners in his sovereignty.
b) Tawhid al-Asma’ was Sifat (lit. “Maintaning the Unity of Allah’s Names and Attributes,”) that is, affirming that they are incomparable and unique.
c) Tawhid al-Ibadah (lit. Maintaining the Unity of Allah’s Worship”) that is, affirming that Allah is alone in His right to be worshiped.
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