The principal deity in the oldest Vedas is Indra, God of the air. In Greek he becomes Zeus; in Latin, Jupiter. The hymns to Indra are not unlike some of the Psalms of the Old Testament. Indra is called upon as the most ancient god whom the Fathers worshipped. Next to India comes Agni, fire, derived from the root Ag, which means "to move."[46] Fire is worshipped as the principle of motion on earth, as Indra was the moving power above. Not only fire, but the forms of flame, are worshipped and all that belongs to it. Entire nature is called Aditi, whose children are named Adityas. M. Maury quotes these words from Gotama: "Aditi is heaven; Aditi is air; Aditi is mother, father, and son; Aditi is all the gods and the five races; Aditi is whatever is born and will be born; in short, the heavens and the earth, the heavens being the father and the earth the mother of all things." This reminds one of the Greek Zeus-pateer and Gee-mêteer. Varuna is the vault of heaven. Mitra is often associated with Varuna in the Vedic hymns. Mitra is the sun, illuminating the day, while Varuna was the sun with an obscure face going back in the darkness from west to east to take his luminous disk again. From Mitra seems to be derived the Persian Mithra. There are no invocations to the stars in the Veda. But the Aurora, or Dawn, is the object of great admiration; also, the Aswins, or twin gods, who in Greece become the Dioscuri. The god of storms is Rudra, supposed by some writers to be the same as Siva. The two hostile worships of Vishnu and Siva do not appear, however, till long after this time. Vishnu appears frequently in the Veda, and his three steps are often spoken of. These steps measure the heavens. But his real worship came much later. The religion of the Vedas was of odes and hymns, a religion of worship by simple adoration. Sometimes there were prayers for temporal blessings, sometimes simple sacrifices and libations. Human sacrifices have scarcely left any trace of themselves if they ever existed, unless it be in a typical ceremony reported in one of the Vedas. § 5. Second Period. Laws of Manu. The Brahmanic Age.