This research began with a question I could not get a satisfactory answer to: do the traditional prohibitions regarding Riba apply to modern fiat currencies in the same manner they applied to gold and silver?

The responses I received from existing literature and practitioners either avoided the structural questions entirely, or defaulted to institutional consensus without engaging with the primary source evidence at the depth the questions demand. So I decided to go back to the beginning and build the analysis from the ground up.

The result is a 119-page research paper that proceeds in a specific sequence, and that sequence matters.

The methodology

This paper does not begin from legal conclusions and work backward. It begins from the Arabic language itself. From the three-letter roots of the words Riba, Qard, Dayn, and Bay'. It builds outward through Quranic usage, Prophetic narration, historical context, and classical scholarly opinion.

Every claim is traced to a primary source. Every scholarly opinion is attributed. Every open question is stated as open, not closed prematurely.

What the paper covers

Part I establishes the precise linguistic meaning of Riba from its root R-B-W / R-B-Y. The root means to grow, to increase, to rise above, to swell, to exceed the original level. Every Quranic occurrence of this root is catalogued and analysed.

Part II traces the four progressive stages of Quranic prohibition, from moral discouragement in the Meccan period to the total and absolute prohibition in the final Medinan revelations, including the declaration of war from Allah and His Messenger against those who persist in Riba.

Part III examines six key Hadith references to Riba, including the Hadith of Riba al-Fadl (the foundational commodity exchange hadith), the Curse on All Parties, and the Farewell Sermon.

Part IV is the longest and most foundational section. It analyses three concepts from their Arabic roots:

  • Qard (the loan): the word means "to cut." A piece cut from wealth, given freely. Only the exact equivalent returns.
  • Dayn (the outstanding obligation): shares its root with Din (faith) and Dayyan (Allah the Judge). A Dayn that grows through delay is Riba al-Nasiah.
  • Bay' (the bilateral exchange): two things moving in two directions. Requires genuine prior ownership, genuine risk, and genuine counter-value on both sides.

Part V addresses form versus substance, examining the question the classical scholars answered and the modern industry will not: when does a trade structure become a disguised loan? Ibn Qayyim and Ibn Taymiyyah are central here.

Part VI surveys the Arabic terms for the medium of exchange in the classical tradition.

Part VII returns to the Hadith of Riba al-Fadl and derives the seven shared characteristics of the six Ribawi items: Mithiliyyah (fungibility), Qimah Dhatiyyah (intrinsic value), Baqa' (durability), Rawaj (universal acceptance), Sifah Ma'lumah (knowable quality), Kayl/Wazn (measurability), and Hajah 'Ammah (essential utility).

Part VIII applies those seven characteristics to fiat currency, one by one. Fiat fails all seven. This is not an assertion; it is the result of the characteristic-by-characteristic analysis.

Part IX examines the Maqasid al-Shariah (objectives of the law) and the fiat medium, focusing on Hifz al-Mal (preservation of wealth) and whether the fiat system itself constitutes a structural violation of this objective.

Part X poses five open questions for scholarly and intellectual inquiry, including: Is fiat currency even the same Jins as gold? Is inflation itself the primary act of Ghashsh, with interest a secondary symptom? Can interest on fiat constitute Riba when the medium itself has no genuine Mithiliyyah?

What this paper is not

This is not a Fatwa. It does not issue rulings. It presents linguistic evidence, historical context, classical scholarly opinion, and analytical reasoning for open scholarly inquiry. The questions at the conclusion are deliberately left open for contribution by qualified scholars, economists, and researchers.

Any errors of interpretation are mine. Any clarity is guidance from Allah alone.

Read the paper

Download the full research paper (PDF)

This research is the foundation on which the Mizan diagnostic tool was built. Mizan takes the four-word framework established here (Riba, Qard, Dayn, Bay') and the seven Ribawi characteristics, and applies them as structured diagnostic questions to any financial arrangement.