The Heart Sutra is the compact Buddhist scripture transmitted to Tang Seng by the Crow’s-Nest Chan Master in Journey to the West. Within the novel it becomes an inward guide for crossing fear and delusion, complementing the maps, companions, and weapons that carry the pilgrimage outward.
Chapter 19 calls it the Many-Heart Sutra, gives its full title as the Prajnaparamita Heart Sutra, and reproduces the text. Tang Seng hears it once and remembers it. The narrator identifies it as a comprehensive scripture of cultivation and a gateway to Buddhahood.
Its narrative role is not a game-like protective incantation. The master says it should be remembered amid demonic obstacles, but the teaching points toward emptiness, freedom from obstruction, and freedom from fear. Its power in the journey is a way of seeing that must accompany physical endurance.