Who are Indra, Vayu, Varuna?

Firstly we need to understand what the term "Gods" mean. In veda he term used is "Deva". Deva is derived from the the word Div[i][/i], to shine or illumine. the devas are beings endowed with consciousness, but without a physical body like humans. thus they are supraphysical beings endowed both with knowledge and power. the seers of vedic age were not just observer of the external world but also of the world within oneselves. each deva is a distinct cosmic power. Indra is the lord of the Divine Mind and Action. In Indian tradition, mind is not the source of knowledge, it manipulates the knowledge to aid action. Indra battles the evil force on behalf of the human. the action of the divine mind, Indra, can be broadly divided into atleast three categories. First task is to manifest knowledge in all humans who have aspired for it. Second task is the preparation and building up of the bodies which can absorb or sustain this knowledge. Third task of Indra is to offer protection for the individuals from the hostile forces. the divine knowledge given by Indra is not meant to come in one step or at any one moment like the experience of samadhi of later vedantic thought. Deva's mentioned in Vedas is quite different and not to be confused with the ones mentioned in Puranas.

The way of the Veda is one of what we call "Arundhati Nyaya". First, I need to explain Arundhati Nyaya. You know the constellation the Great Bear. This consists of Seven Stars - Four of them forming a Quadrilateral with a Tail of Three stars. In the Hindu mythology this constellation is called Saptarshi Mandalam- or the congregation of the Seven R^ishis(=Seers). As I have said in several other posts in the Vedas the Prophets are called Seers. This is because they are said to have apprehended Reality as clearly as a person of very good eyesight "sees" ordinary concrete things. Near the head of the GB which is identified as Atri-R^iShi, is his consort Arundhati whose chastity and devotion to her husband gave her not only the highest reverence among followers of the Hindu faith, but great powers. In the Hindu Thought/Mythology a chaste married woman is a formidable power to reckon with. This Arundhati is such a faintly luminous star that for someone to see it people show something easy to identify in the visual field like, say a tree top. Then they show the GB constellation, the tail the head and so on. The goal is to spot Arundhati but you go through some easy steps so that in the final step you reach where you want to. The path to the Realization of God [called Brahman in Veda/Vedanta] is something like that. The seeing of Arundahti is an important ritual in Vedic Marriage. The newly-weds are exhorted to take Atri-Arundhati as their role model in life. Thus the Vedas talk of several Gods, said to be "presiding" over some part of Nature. Hence Indra becomes the God of Rain. He is also the King of Gods according to the Puranas. The hymns of the RgVeda are addressed to the 33 Pricipal Gods of the Vedic Pantheon. Thus Indra is the Rain-God. Vayu the Wind-God, Varuna is the Sea God. But these are all a tier-1 modelling of the concept that the Veda is trying to take you through. Max Mueller thought this is the final idea and called the Vedic R^ishis as Nature Worshippers. He equated the Vedic Hymns to some kind of Pastoral Poetry. That is sad. Now, there is a tier-2 meaning. Indra is the Lord of the Senses. There are several hymns in the Rig Veda, that "pray" for perfectly active senses till one's ripe Old Age is reached. There, the God to which such prayers are addressed is Indra. Thus at a subtler level than we started with Indra has been moved on from Rain God to Lord of the Senses. Like wise Vayu the Wind-God becomes the various energies that control the various metabolic action in living beings. Similarly Varuna represents the Harmones/Fluids in the body. Thus by working tier after tier of meanings the Veda zooms and pans you through the subtler and subtler concepts till the nearly incomprehensible abstractions are met in the Upanishads. Thus every Mantra in the Vedas is in effect a hologram. The Veda is the hologram of all Universe,Life and Intelligence to name a few. That is why the Hindus hold Vedas as God. This is evidenced by the mantra also being reffered to by the word Brahma(n) just as is God. I think I should stop here. I can go on and on till this editorial buffer is full.

As the responder before me has already said, Indra being the King of Gods (somewhat like Zeus) was given more importance than the other Gods...but he and the other Gods are a rung lower than the ultimate trinity of Brahma, Vishnu and Maheshwar. So naturally the Vedas dedicate a lot of hymns to these Gods coz Vedas are from a time when nature worship was the ultimate and only religion. Indra was supposed to be the god of rain and thunderstorm so he was quite important for an agrarian society. What's interesting though, is the distinct similarity between the Gods of Vedic Hindus and the ancient Greeks/Romans...the pantheon of Gods is there in both and note particularly Zeus/Indra...both gods of rain and thunder.

Indra is the king of Gods. So naturally he is given importance than other gods. But he is not one of the supreme gods who are Lord Siva, Maha Vishnu, and Brahma. But there are stories where this Indra who is respected becomes too full of himself and thinks he is too great, gets his fat head emptied by some others. I think he represents people who have the potential and are great but at times pride enters their minds. Then Vayu is the god who takes care of air(in sanskrit it is called vayu), Varuna is the god of rain. Vayu and Varuna are sub gods with specific duties where as Indra is the king of gods. Happy mylotting n god bless u.