Buddhism, once a dominant religious and cultural force in its birthplace of India, experienced a dramatic decline between the 7th and 13th centuries CE, eventually nearly vanishing from the subcontinent. This research examines the multifaceted causes of this "symbolic paradox," analyzing the intersection of external pressures and internal vulnerabilities. External factors included intense competition and strategic absorption into Brahmanical symbolism, in which the Buddha was recast as an avatar of Vishnu, and the decisive military destruction of major monastic universities, such as Nalanda, by Muslims. Internally, Buddhism suffered from sectarian fragmentation, a growing disconnect between monastics and the laity, and a shift toward complex scholasticism that alienated common followers. Despite its retreat from India, Buddhist symbols survived through migration to Tibet, East Asia, and Southeast Asia, and, significantly, through the emergence of Giao Chau Buddhist symbols (Vietnam today) via Tứ Pháp (Four Dharma). This research hypothesizes that although the institutional conditions for Buddhism can be fragile, its core teachings possess resilient symbolism that enables them to re-emerge across diverse cultural and social contexts and in different modes of practice.