The Ottoman Empire in its last decade shifted from Abdulhamid II’s Islamist policies to Young Turks’ nationalist and secularist government. This transformation changed not only the Ottoman polity but also the dynamics of the intellectual circles. A young and ambitious member of the newly emerging Turkist intellectual circles was Halim Sabit (Sibay), whose intellectuals activities are largely ignored in the late Ottoman historiography. As a madrasa professor with a strong education in Islamic law Halim Sabit was in a distinct position to provide Islamic justifications for the Young Turk government and its secularization efforts. During the years of World War I Halim Sabit worked as the editor of the biweekly Islam Mecmuasi which increasingly and ardently laid the intellectual grounds for secularization. Focusing on Halim Sabit’s views on ijtihad as expressed in the late Ottoman journals Sirat-i Mustakim and Islam Mecmuasi this paper argues that ijtihad was the key concept within the Islamic legal terminology which Halim Sabit utilized to justify secularization in the late Ottoman Empire. A fervent defender of ijtihad Halim Sabit argued that only by reviving ijtihad can Muslims adapt to the modern conditions. For Halim Sabit, ijtihad was very much needed in the contemporary Muslim world and it had become an inevitable solution to prevent the demise of Muslims. After a discussion of the historical evolution of the concept of ijtihad Halim Sabit concluded that the Tanzimat Reforms had to be carried further by reducing the powers of religious authorities to the realm of religious worship only and expanding the powers of the secular ministries to all the realms of the state. A detailed look into Halim Sabit’s schema of a secular Ottoman state helps better understand the intellectual background of the secularization in the late Ottoman Empire and the later Turkish Republic. Published articles in Sirat-i Mustakim and Islam Mecmuasi as well as Halim Sabit’s personal notes and library constitute the primary sources for this paper.