Interfaith harmony encourages followers of various faiths to live peacefully together in a cordial atmosphere. Religious leaders, theologians, and ulema have recently been involved in the interpretation of holy scriptures to suggest ways for advancing interfaith harmony. Contemporary religious thoughts have gradually reached the level of appreciating religious diversity. From the Western concept of religion in singular to recognition of religious diversity, contemporary theologians have moved through various stages such as true and false religions to Nostra Aetate. The study is not only describing basic concepts related to interfaith relations and their significance but also unfolding evolution of contemporary thoughts on interfaith harmony in various theologies. The notion of discourse analysis and the nature of contemporary interfaith relations have also been illustrated in the study. The study proceeds with the elaboration of various conceptions such as religion, interfaith dialogue, interfaith harmony, religious diversity, and religious pluralism. Due to globalization and increased religiosity, inter-religious interactions have amplified throughout the world. Consequently, the growing interest in interfaith harmony urges religious scholars to give their reviews on the various dimensions of interfaith dialogue. The study also contains opinions that contributed to the emergence of contemporary thought on interfaith harmony. Muslim scholars have also been trying to the layout of the concept of interfaith harmony from the perspective of the Holy Qur’ān and Sunnah of Prophet Muḥammad (Peace Be Upon Him). It is expected that the study will contribute to highlighting the importance of interfaith relations in the contemporary Muslim world.