The Syrian Christians of Kerala, one of India’s ancient Christian communities, trace their origins to the evangelization of Thomas the Apostle. During the colonial era, European missionaries sought to reform this community by vernacularizing the Syriac liturgy. Through printed hymnals and catechetical formation, Carnatic music, the classical tradition of South India, was integrated into Christian worship. In post-independence India, the Church institutionalized this practice through competitions that promoted Carnatic compositions and trained generations of musicians. Building on scholarship on vernacular Christianity and South Indian classical music, this paper traces the trajectory of Carnatic music among Kerala’s Christian communities, examining continuity and change in its adaptation across colonial and postcolonial contexts. While Carnatic music is often framed as an exclusively Hindu art form, this study shows how Christian composers and performers reshaped it as a vehicle of devotional expression and communal identity. In contemporary India, this tradition faces renewed tension as hate campaigns target performers of non-Hindu Carnatic compositions, reflecting Hindutva ideology that seeks to define classical music within a Hindu framework. By historicizing Christian encounters with Carnatic music from colonial translation to contemporary resistance, this paper challenges assumptions about Indian classical music as religiously bounded. It demonstrates how Christian musicians navigate cultural and political pressures while continuing to create and perform, offering a model for understanding how minority communities inhabit and transform majoritarian musical traditions. The study contributes to ethnomusicological debates on music, religion, and cultural nationalism while foregrounding sound as a site of devotion and contestation in modern India.