Not only do the poets often couple the two gods in prayer and praise, but they often tell us that the one performed his characteristic deeds by the help of the other. They say that Vishṇu made his three strides by the power of Indra (VIII. xii. 27), or for the sake of Indra (Vāl. iv. 3), and even that Indra strode along with Vishṇu (VI. lxix. 5, VII. xcix. 6), and on the other hand they tell us often that it was by the aid of Vishṇu that Indra overcame Vṛitra and other malignant foes. "Friend Vishṇu, stride out lustily," cries Indra before he can strike down Vṛitra (IV. xviii. 11).[14] The answer to this riddle I find in the Brāhmaṇas, the priestly literature which is about to follow immediately after the Vēda. In plain unequivocal words the Brāhmaṇas tell us again and again that _Vishṇu is the sacrifice_.[15] Evidently when they repeat this they are repeating an old hieratic tradition; and it is one which perfectly explains the facts of the case. Vishṇu, I conceive, was originally nothing more or less than the embodied spirit of the sacrificial rites. His name seems to be derived from the root _vish_, meaning stimulation or inspiration; and this is exactly what the sacrifice is supposed in priestly theory to do. The sacrifice, accompanied by prayer and praise, is imagined to have a magic power of its own, by which the gods worshipped in it are strengthened to perform their divine functions. One poet says to Indra: "When thy two wandering Bays thou dravest hither, thy praiser laid within thine arms the thunder" (RV. I. lxiii. 2); and still more boldly another says: "Sacrifice, Indra, made thee wax so mighty ... worship helped thy bolt when slaying the dragon" (III. xxxii. 12). So it would be very natural for the priests to conceive this spirit of the sacrificial rites as a personal deity; and this deity, the Brāhmaṇas assure us, is Vishṇu. Then the idea of the three strides and the association with Indra would easily grow up in the priestly imagination. The inspiring power of the sacrifice is supposed to pervade the three realms of the universe, earth, sky, and upper heavens; this idea is expressed in the common ritual formula _bhūr bhuvas svaḥ_, and is symbolised by three steps taken by the priest in certain ceremonies, which are translated into the language of myth as the three strides of Vishṇu.[16] Observe that in the Ṛig-vēda the upper heaven is not the dwelling-place of Vishṇu only; Agni the Fire-god, Indra and Sōma have their home in it also (RV. I. cliv. 6, IV. xxvi. 6, xxvii. 3-4, V. iii. 3, VIII. lxxxix. 8, IX. lxiii. 27, lxvi. 30, lxviii. 6, lxxvii. 2, lxxxvi. 24, X. i. 3, xi. 4, xcix. 8, cxliv. 4). Later, however, when their adventitious divinity begins to fade away from Agni and Sōma, and Indra is allotted a special paradise of his own, this "highest step" will be regarded as peculiar to Vishṇu, _Vishṇōḥ paramam padam_. [Footnote 14: A later and distorted version of this myth appears in AB. VI. xv.]