Maharshi Marichi was the son of Lord Brahma. Prajapathi who was the son of Maharshi Marichi married 13 daughtersof King Daksha. Diti devi was the most elder among them. Hiranyaksha and Hiranyakasipa were the two sons of Diti devi. As they grew up they were habituated to cruelty towards all the world and were demons by character. Lord Maha Vishnu in His Varaha avatara and Narasimhavatara got rid of them for the protection of the world. Diti devi who was sad about the ďeath of her children served kasyapa and concieved. Lord Indra who was afraid that Diti may give birth to another demon entered into her womb and destroyed the foetus with his vajrayudha by making it into seven pieces. Again he cut each piece into seven pieces. Still the foetus survived because of the Shiva vrata phala done by Diti devi. The broken parts of the foetus were born as Saptha Maruttulu. They went to swargaloka and were among Indra parivara.
Diti devi once again went to her husband Kasyapa and requested him to bless her with children. Kasyapa advised her to do penance for Lord Shiva for ten thousand years. Obeying her husbands order Diti devi did a great penance for Lord Shiva and with his blessings served her husband gave birth to Vajranga. His body was as tough as diamond (vajra) and was a great warrior . Diti devi wanted her son to defeat Indra. Vajranga obeyed his mothers wish and defeated Lord Indra and conquered swargaloka. Diti devi was happy that her son defeated Lord Indra. Lord Indra and all other dieties were prisoned by Vajranga and were punished. Lord Brahma came to know about Vajranga and He went to Vajranga with Kasyapa who was his father. Lord Brahma told to Vajranga that it was not fair to occupy swargaloka and ordered him to let all the dieties free. Vajranga said that Indra was bad and he was the person who broke my mothers baby into pieces in her womb. That is why I punished him. Vajranga obeyed Lord Brahma and he left Lord Indra and his parivara who were prisoned. Vajranga said that he was not interested to conquer any rajya but he was just obeying his mothers wish . He requested Lord Brahma to teach him about "Tatwagnana".Lord Brahma was happy with Vajrangas request and told him that "satwika swabhava"(satwa is one of the three gunas satwa, rajas , tamas) is the essence of Tatwagnana. Lord Brahma also created Varangi and gifted her to Vajranga and went back to his Loka. From then Vajranga practised satwika swabhava and he left all his demon behaviour and was without enemies. But his wife could not be like him and served him with kamabhava.
