Indra the misunderstood diety and tantra of Indra
Indra is not regarded as an uncreated deity. In some hymns in Vedas he is spoken of as the twin-brother of Agni, and therefore the son of Heaven and Earth; whilst, in other hymns, heaven and earth are said to have been formed by him. Although his parents are often referred to, it is but seldom that they are named; and when they are named, they are not always the same. He is the king of the gods; and in post-Vedic ages,
his reign is said to extend for a hundred divine years only; at the end of which time he may be superseded as king by some other of the gods, or even by man, if any be able to perform the severe penance necessary to obtain this exalted position. Indra is said to be the presiding diety of Vishakha nakshatra and Jyeshtha. Lord Indra is the most misunderstood diety in Purans, though he is said to be king of gods, king of heaven, king of thunder and storm. In tantra he is said to be the lord of "sudden awakening" like a thunderbolt. He is also the controller of "5 elements" just like shiva, and depicts the "Akash element" . But with him comes the tag like "soma addict", "pervert", "jealous”, “arrogant", "sex monger" characterless etc. The iconology of Indra is a post, a designation of a king, which can be replaced. performing 100 Ashvamedha Yagnas, any man can go to heaven and can obtain position of the king of heaven.
One day of Brahma is approx. 4.3 billion human years (100
0 Chatur yugas). This is divided into 14 manvantaras (period ruled by different Manus). For each Manvantara, the positions of Indra, Saptharishis (7 great sages) etc. will be occupied by different people. Here is a brief list (as per Srimad Bhagavatam):
Swayambuva Manu: Yagna was Indra (Yagna was
a partial incarnation of Lord Vishnu)
Svarochisa Manu: Rocana was Indra
Priyavrata Manu (grandson of Swayambuva Manu): Satyajit was Indra
Tamasa Manu: Trishikha was Indra in this period
Raivata Manu: Vibhu was Indra
Caksusa Manu: Mantradruma
Vaivasvata Manu (Current Manu): Purandhara
Savarni Manu: Bali Maharaja will be the next Indra (the same Bali maharaja who offered 3 feet of land to Lord Vamana)
Daksa Savarni: Adbhuta will be Indra
Brahma Savarni: Sambhu
Dharma Savarni: Vaidhrta
Rudra Savarni: Rtadhama
Deva Savarni: Divaspati
Indra Savarni: Suci will be the 14th Indra
Indra being the presiding diety of Jyeshtha naksh
atra and partially over Vishaka along with agni natives of these nakshatra(Scorpio ascendant) can relate to the blames Indra received. So these nakshatras cannot remain confined to narrow mindset, or limited understanding of things. Indra Tantra is all about ruling over the good and bad within yourself and be accepting of the evil that the mind creates, but also getting up as a thunderbolt to shun it ff, when one needs to fight against evil. Indra tantra doesn't allow you to be at peace, it is the indicator of a proactive mind, a mind that wants to work all the time. Indra is the perfect symbol for " work hard, party harder" in kalyug.
In Rig Ved, Indra defeats Vritra(the demon of drought), some also say Vritra the snake-personified demon represented fog and clouds, obstructing the sun. So Indra is the removal of obstruction the fog/blindfold in a person's mind. Also since Indra is said to represent Akasha element, when Indra strikes Vritra(cloud) with his thunderbolt, rainfall happens. Hence Indra is said to be the god for crops, rains, and prosperity.
Adhyatmik explanation: " Word Indra is originated from the dhatu "Indha" as per Shatapatha Brahmana, so is the word Indhan(fuel/ignitor). Indha means the one who ignites.Indra is the brighter consiousness (divya chetna) which gets lit when hit with a thunderbolt. Vritra on the other hand originated from "Vri". Avrit here means one who covers, or envelopes. So here demon Vritra is ignorance/avidya. So here Indra winning over Vritraasura means destroying ignorance with the fire of atma gyan(self realization). Indra means having a control over all Indriyas(senses). Yogis say "Indhe Bhutani", i.e the energy behind activeness of Panch Bhutas. His thousand eyes represents close self introspection and vigilence of every nook and corner of existence. Hence he is called the "Sahasraksha purusha". Sanskrit language has vast scope of application and different contextual meaning. These terminologies have adhyatmik, adhidaivik and adhibhautik meanings. Vedic Rishis used them in a allegorical way, and is used in Vedas, Yoga, Tantra or any Hindu scripture. So the interpretation around Indra is often misunderstood, the text around Indra needs deeper decodation, interpretation and understanding