<![CDATA[Purpose - Interfaith marriage in Indonesia continues to generate theological, juridical, and socio-legal debates, particularly in the context of legal tensions surrounding Law No. 1/1974 and the Compilation of Islamic Law (Kompilasi Hukum Islam). While previous studies have predominantly approached this issue from legal and sociological perspectives, the epistemological function of ḥifẓ al-dīn (protection of faith) within a systematic Qur'anic framework remains insufficiently explored. This study investigates how the Qur'an conceptualizes interfaith marriage through the objectives of Islamic law (maqāṣid al-sharī'ah), with particular emphasis on faith preservation. Design/methodology/approach - The study employs a qualitative library-based approach using thematic Qur'anic exegesis (tafsīr maudhū'ī) integrated with the maqāṣid al-sharī'ah framework. The analysis focuses primarily on QS. al-Baqarah [2]:221 and QS. al-Mā'idah [5]:5, complemented by classical and contemporary exegetical sources, Islamic jurisprudence, and modern hermeneutical perspectives to evaluate the teleological objectives underlying the relevant legal rulings. Findings - The study demonstrates that the Qur'anic prohibition of interfaith marriage functions not merely as a legal restriction but as a preventive mechanism for safeguarding faith, preserving spiritual stability, and ensuring intergenerational transmission of Islamic values. It further argues that classical juridical concessions regarding marriage with the People of the Book (Ahl al-Kitāb) require contextual re-evaluation in contemporary socio-legal settings through the principle of taqyīd al-mubāḥ for the realization of maṣlaḥah (public welfare). Research implications/limitations - The analysis is confined to Qur'anic theological and maqāṣid-based perspectives and does not include empirical investigation of contemporary interfaith families. Future research may integrate doctrinal and socio-empirical approaches across diverse Muslim societies. Originality/value - This study contributes to Qur'anic legal scholarship by positioning ḥifẓ al-dīn as the central epistemological rationale underlying the Qur'anic regulation of interfaith marriage. It offers a teleological framework that bridges thematic exegesis, maqāṣid al-sharī'ah, and contemporary Islamic family law, providing conceptual guidance for legal policy, premarital counseling, and the development of Islamic family regulations in pluralistic societies.]]>
