Muhammad ‘Abduh (1849-1905) is mostly considered a modernist or reformist (salafi) Muslim thinker as opposed to being traditionalist or conservative. However, it is not easy to categorize him, as his work presents signs of both modern and traditional genealogies. He lived in a high period of reform in both the Ottoman Empire and Egypt. He joined struggles to combine European modernity with Islamic tradition. In order to demonstrate his struggle, I focus on Abduh’s ideas in his book Risalat al-Tawhid (Treatise of Unity), which was published in 1897 (two years before he became Mufti of Egypt). While it is a treatise on systematic theology, it has a somewhat different content compared to traditional theological works. He argues that contemporaneous ilm al-tawhīd (theology) books did not meet the expectations of students of the time. Thus, he saw a need to rearticulate theological issues using terms familiar to that level of students and he united thoughts both from classical theological scholars as well as modern thinkers. By analyzing Muhammad Abduh’s ideas in this book, I compare his views on religion, first with a European intellectual, Auguste Comte (1798-1859), and then with a thinker from Islamic tradition, namely Sa’ad al-Din al-Taftazani (1322-1390) in his Sharh al-‘Aqaid. In Risalat al-Tawhid, ‘Abduh seems to have benefited from Enlightenment ideas about history. Like Comte, ‘Abduh sees a progress in human civilization, from the primitive to a rational and modern society. In other words, religious development parallels human progress. On the other hand, both ‘Abduh and al-Taftazani have the same kind of modalities in their classification of existence and knowledge. In short, comparing Abduh’s views together with those, we can better understand his approach in relation to classical and modern conceptions of religion. Therefore, I interpret his Risalat al-Tawhid as a way of reformulating classical understanding of theology while experiencing modernity under the colonial rule.