Dyaus is derived from the root div (to shine) and means effulgent. The word means ‘sky’ in about 500 places in Rig Veda. It is surprising that there is not a single hymn addressed to it Dyaus as God. Mostly it comes in the company of prithvi (the earth) and the compound is dyavaprithvi sometimes dyavaprithvyau.
Dyavaprithvi as dual deities are praised in six hymns (Rig Veda VI.159, 160, 185; IV.56; VI.70 and VII.13). Both of them together protect the ritual there and grant wealth liberally to devotees. They are parents of gods (1-159, 1-3). The adorable Dyavaprithvi are prayed to give strength, fame and progeny to the performers of rituals (I.160.5). Both of them are requested to dyava raksatam no prithvi abhavat (save us from suffering) (I.185.2-8).
Sometimes they are presented as sisters (I.185.1, 2, 5). The performer of the ritual invites both of them respectfully by bowing. (I.185.6, 7). They are offered oblation and panegyrics (IV.56.2,3) and are prayed to, to get in return a good wife and a spacious habitat (IV.56.4). They are appealed to have friendship with the offerer (IV.56.7). They are adored with many praiseworthy attributes (VI.70.1-3) and are requested to grant progeny and abundant wealth to the performer of the ritual (VII.70.6)
In other hymns the dual deities occur many times. When the word dyaus occurs alone, it invariably means, ‘father’. Dyaurastu nah pta (Let Dyaus be our father)(I.70.7). Dyaurme pita (Dyaus is my father) (I-164.33), Dyauspita janita (Dyaus is the father creator IV.1.10).
Like other gods he is called Asura (the mighty) (I.131.1). Usha (the dawn) is his daughter and Ashwini Kumars are his sons. Dyausat times gives the meaning of the personified heavens or Father Heavens.
Dyaus is Supreme Father (I.71.5). He is said to be a mighty bull roaring loudly (I.160.3, V.36.5, 55.6). Some human features are imposed on him when he is said to be asanimat (adamant) and smiling through clouds (II.4.6). Perhaps lightening is called the smile in the sky.
The similarity between Dyaus and Zeus, the Supreme national divinity of Greece, had lead some scholars to believe in their identity. But other scholars have rejected the same. The similar analogy is given between Dyauspitar and Jupiter, the chief of God of Romans and one of the brightest planets but this appears as impossible, though some of their attributes may be common.