The Maha Mrityunjaya, the great death-conquering mantra, is a Vedic verse (Rig Veda 7.59.12, also carried in the Yajurveda) addressed to Tryambaka, the three-eyed one, an epithet of Rudra that later tradition reads as Shiva. Its imagery is agricultural and precise: it asks to be freed from the bondage of death as a ripe cucumber is freed from its stem, not clinging, so that release is figured as a natural loosening rather than a violent break. It prays for nourishment and long life while accepting the eventual parting.
In practice it is recited over the sick and the dying, at times of danger, and as a general protective and healing formula, often repeated in counts of 108 on a rosary (mala). Because it is a canonical Vedic verse rather than a later composition, it carries the authority the tradition attaches to shruti, revealed sound, and it is one of the most widely used of the Vedic mantras that have passed into everyday devotional life. Its power is held to lie as much in the exact sound of the recitation as in the meaning, which is the general premise of mantra in the Indian traditions.