This scholarly work by Dr. Nasruddin bin Sarray provides an in-depth analysis of Abu Hamid al-Ghazali's intellectual framework, focusing on the core concept of Tawhid (divine unity). The book meticulously explores how this monotheistic vision serves as the foundation for epistemic integration in al-Ghazali's philosophy. Sarray examines al-Ghazali's writings to demonstrate how he harmonized various fields of knowledge—from the rational sciences to spiritual insights—under a unified theological worldview. This study is essential for understanding the profound connection between faith, reason, and the pursuit of holistic knowledge in classical Islamic thought.