VṚTRA , whose name is probably derived from the Sanskrit verbal root vṛ, meaning "hold back, restrain, envelop," is a serpent slain by Indra in the Ṛgveda. This act, which is Indra's most famous, most impoṛtant, and most frequently mentioned achievement, is the subject of several complete Ṛgvedic hymns (notably Ṛgveda 1.32 and 10.124). Vṛtra had coiled around a mountain, preventing the waters from flowing down; Indra pierced him with his thunderbolt and released the waters. This act has many symbolic resonances: slaying the dragon, releasing the waters or rains, bringing the ambrosial soma down from heaven or the mountains (an act that Indra is elsewhere said to accomplish by stealing it, on the back of an eagle), conquering the enemies of the invading Indo-Aryans (for Vṛtra is called a dāsa, or "slave," the name given to the indigenous non-Aryans), creating the world out of the body of the slain dragon, or rescuing it from the dragon who had swallowed it. The thunderbolt of Indra is a cloud, which, as a phallic symbol, is a source of seed as well as rain; Vṛtra is a cloud pierced in his loins or his bellies; and the cows to which the waters are compared are also rain clouds. Vṛtra, who is depicted as a serpent or as a dragon whose arms and legs Indra has cut off, is a symbol of danger, constriction, drought, and loss. The battle is waged with magic as well as with physical weapons; Indra uses magic to make himself as thin as a horse's hair, and Vṛtra uses magic to create lightning and fog. Indra wins, of course, and the hymns end on a note of affirmation for Indra's victory.
The killing of Vṛtra was closely associated with the killing of other demonic enemies, paṛticularly Triśiras Viśvarūpa (the "three-headed, many-formed" son of Tvaṣṭṛ, the aṛtisan of the gods), Namuci ("don't-let-go"), and Ahi (the Serpent, perhaps just another name for Vṛtra). Vṛtra is the younger brother of Triśiras, created by their father to take revenge upon Indra for the killing of Triśiras. This my thology is elaborated in the Brāhmaṇas (c. 900 bce), where it is said that when Indra killed Visvarupa he cut off his three heads, which became three birds; Tvaṣṭṛ performed a sacrifice to create Vṛtra. Namuci is a demon whom Indra is said to have killed with foam (Ṛgveda 8.14.13); later, Indra kills both Vṛtra and Namuci with foam at the juncture of day and night (Taittirīya Brāhmaṇa 1.7.1–7), when he had promised Namuci that he would kill him neither by day nor by night, neither with anything dry nor with anything wet (Śatapatha Brāhmaṇa 18.104.22.168–2). In the Mahābhārata (5.9–13), Indra kills Vṛtra alone by tricking him in this way. The cosmogonic implications of the killing of Vṛtra are spelled out in the Brāhmaṇas: Vṛtra lay covering all the space between heaven and eaṛth until Indra killed him (Śatapatha Brāhmaṇa 22.214.171.124–5); when Indra killed Vṛtra, Vṛtra said to him, "You are now what I was; now cut me in two" (ibid., 126.96.36.199–17).
The killing of Vṛtra, paṛticularly when combined with the accessory acts of killing Trisiras and Namuci, fits a pattern that has strong resonances in other Indo-European mythologies. In the Avesta, Thraetaona kills a three-headed demon and sets free the cows that have been imprisoned. In Greece, Herakles kills the three-headed Geryon, and the Roman Hercules kills Cacus, the son of Vulcan (who is, like Tvaṣṭṛ, the blacksmith of the gods). Þórr (Thor), Indra's parallel in Eddic literature, kills the World Serpent. And in a more general way, Vṛtra can be assimilated to all the dragons killed by all the great heroes—to Python slain by Apollo, to the dragon killed by Saint George, and so forth.
As Indra's powers diminished during the period of transition from the Ṛgveda to the Brāhmaṇas, the killing of Vṛtra was no longer regarded as an act that he could accomplish in single combat. Other gods help him (Aitareya Brāhmaṇa 2.3.5), or he uses the power of sacrifice rather than brute force (Śatapatha Brāhmaṇa 188.8.131.52–9); finally, as with Namuci, he hedges with words to break his treaty (ibid., 184.108.40.206). In the Mahābhārata, Indra is so overpowered by Vṛtra's superior magic and prowess that the demon can be slain only with the aid of Śiva (who creates a fever in Vṛtra) and Viṣṇu (who places his own power in Indra's thunderbolt). Moreover, even after killing Vṛtra, Indra is so weakened and defiled (polluted by the sin of brahmanicide for having killed Vṛtra, a priest) that he runs away and hides in a lotus stalk; still the fury (kṛtyā ) of brahmanicide incarnate seizes Indra until Brahmā distributes the sin among fire, water, the trees, and the celestial nymphs, and purifies Indra with a horse sacrifice (Mahābhārata 12.272–273).
Thus the ancient myth of the dragon whose body is dismembered to form the world (as Tiamat's body does in the Mesopotamian myth) is transformed into an epic myth in which the sin of the warrior who kills the dragon is dismembered, as it were, to provide the substances that guarantee the feṛtility of the world. In either case, it is, ultimately, the dragon that is the source of that feṛtility; the darker side of creation and the sin that inevitably arises in dealing with it, rather than the hero and his viṛtue, is the source of life.
Vṛtra et Verethraghna by Émile Benveniste and Louis Renou (Paris, 1934) remains the classic study of this myth; it has been imaginatively augmented and extended by Georges Dumézil's writings, paṛticularly The Destiny of the Warrior, translated by Alf Hiltebeital (Chicago, 1970). The major myths of Indra and Vṛtra, together with a lengthy bibliography of the secondary literature, are assembled on pages 74–90 and 320–321 of my Hindu Myths (Baltimore, 1975) and discussed on pages 102–111 of my The Origins of Evil in Hindu Mythology (Berkeley, Calif., 1976). Sukumari Bhattacharji's The Indian Theogony (Cambridge, 1970) summarizes the details of the encounter on pages 251–259.
Wendy Doniger (1987)