The Dilemma of Global Hijri Calendar Unification: The Dialectic of Fiqh and Astronomy in Realizing The Standardization of The Modern Islamic Calendar

Abstract

Differences in determining the beginning of lunar months among Muslim countries remain a persistent and unresolved issue in the modern era. Efforts to unify the global Hijri calendar face a dilemma between the authority of fiqh based on traditional ru’yah (moon sighting) and the accuracy of modern astronomical calculations (hisab). This study aims to examine the dialectic between these two approaches in order to formulate a scientifically sound and sharī‘ah-compliant framework for Islamic calendar standardization. This research employs a qualitative library-based method with a descriptive–comparative approach, analyzing classical and contemporary fiqh literature, resolutions of the Organization of Islamic Cooperation (OIC), and astronomical data from institutions such as MABIMS, ICOP, and the International Astronomical Union (IAU). The data analyzed include hilal visibility criteria, contemporary hisab systems, and decisions of religious authorities across various Muslim countries.The findings show that the stagnation of Hijri calendar unification is driven by epistemological differences between ru’yah and hisab, institutional fragmentation among religious authorities, and the absence of an integrative framework linking maqāṣid al-sharī‘ah with modern astronomical methodology. This study contributes by proposing a scientific–theological integrative framework based on maqāṣid al-sharī‘ah and global moon visibility as a normative and empirical foundation for a unified, accurate, and equitable Hijri calendar.