Few social structures have shaped Indian history as deeply as caste. It determined: • status • occupation • access to temples • marriage • learning • dignity Yet within Indian spiritual history, some of the most luminous voices rose in rebellion—not political rebellion, but spiritual rebellion. They declared: The soul has no caste. God recognizes no hierarchy. Birth cannot determine truth. Among these voices, two poet-saints stand as giants: • Kabir (15th century North India) • Yogi Vemana (Telugu poet-saint of South India) Separated by geography and language, both arrived at the same realization: Spiritual worth is not inherited. It is awakened. This article explores how Kabir and Vemana challenged caste through the deepest weapon available: spiritual insight expressed in poetry.