This thesis will examine the re-emergence of debates on ribā (i.e. bank interest in today's economy) after the 19th century in Muslim societies. To explain this re-emergence I will focus on the intersection of Islamic law with social changes in the context of modernity capitalism reform and Islamism. I shall divide my thesis into two parts. The introduction of the thesis will generally review both the theoretical and conceptual basis for the Islamic textual responses to interest-bearing (ribawī) transactions. The first part while largely analyzing the methodology of Fazlur Rahman (1919-1988) as a reformist will focus on how modernity has affected the process of interpretation of Islamic texts making law and issuing fatwas since the 19th century. The second part focusing on Abū al-Aʻlā Mawdūdī (1903-1979) as an revivalist will deal with the alternative solution which we shall call the moral economic system of Islam (al-niẓām al-iqtiṣadī al-Islāmī) to the issue of bank interest as opposed to the reformist interpretation of Islam and the Western type of banking system. The main purpose of this thesis is to analyze the two leading Muslim scholars' attitude towards the rapidly expanding economic system.