Tawheed (Divine Unity) is the core of Islamic doctrine and the foundation upon which the intellectual and faith-based structure of Islam rests. No act of worship or deed is accepted except through the oneness of Allah Almighty and by declaring Him free of any partner or imperfection. This fundamental creed was clearly manifested in the discourses of the Imams of Ahlul-Bayt (peace be upon them), most notably Imam Ali ibn al-Husayn Zayn al-Abidin (peace be upon him), whose supplications and sermons represent a comprehensive school of thought in consolidating the concept of Tawheed through a profound spiritual and philosophical approach. *Tawheed in the Thought of Imam Zayn al-Abidin (peace be upon him)* Imam (peace be upon him) viewed Tawheed not merely as a verbal affirmation, but as an existential state lived by a person in both consciousness and conduct. To him, Allah Almighty is the First with no beginning, and the Last with no end. He is not perceived by sight, nor can minds comprehend Him. He is the Absolutely Self-Sufficient who has no need of anything, while everything besides Him is in need of Him at every moment. The Imam particularly emphasized in his supplications, especially in _Al-Sahifa al-Sajjadiyya_, the transcendence of Allah beyond resemblance and anthropomorphism. He affirmed that no matter how far minds advance, they cannot grasp the Essence of Allah. They can only perceive His effects in creation, in its order, and in the precision found throughout the universe. *Tawheed in Supplication and Spiritual Discourse* The discourse of Imam Zayn al-Abidin (peace be upon him) was distinguished by its profound spirituality, as he made supplication an educational means to firmly establish creed. In his intimate prayers, Tawheed appears clearly when he binds the servant completely to his Lord. He shows that every power in life is from Allah, every blessing is from Him, and every removal of affliction is in His hand alone. The Imam also nurtures people upon practical Tawheed, meaning reliance upon Allah without turning to causes as if they act independently, but rather regarding them as instruments placed at the service of Allah’s will. *Dimensions of Tawheed according to the Imam (peace be upon him)* The dimensions of Tawheed in the discourse of Imam Zayn al-Abidin (peace be upon him) can be summarized as follows: 1. *Tawheed al-Dhati – Essential Oneness*: Affirming the oneness of Allah and declaring Him free of any partner. 2. *Tawheed al-Sifati – Oneness of Attributes*: His attributes are identical with His Essence and are not separate from Him. 3. *Tawheed in Creation and Lordship*: Allah is the sole Creator and Manager of the universe. 4. *Tawheed in Worship*: None is worthy of worship except Allah alone. *Conclusion* The discourse of Imam Ali ibn al-Husayn (peace be upon him) represents a complete school in consolidating the concept of Tawheed, as it combines doctrinal depth with spiritual and educational dimensions. His supplications contributed to building a faith-based awareness that makes a person more connected to Allah Almighty, and more aware of the reality of existence, which is based on the oneness of the Creator and His absolute and unique perfection. M.D. Hameed Ali Mansour Al-Talqani