Lord Brahma had created Daksha from the thumb of his right hand. Daksha’s wife was created from the thumb of Brahma’s left hand. Daksha had a daughter named Aditi. Martandadev was the son of Aditi and his father was Kashyapa.
Kraustuki asked- ‘O lord! Why did Vivasvan Surya took birth as the son of Kashyapa.’ Markandeya says- ‘During the initial phase of creation, when nothing existed, except a large egg.
Lord Brahma manifested inside that egg. Subsequently, he came out from that egg. At that time, a loud sound of OM came out from his mouth. From this sound of Omkar, were created Bhur, Bhuvah and in the end Swah. These three mystic words are the forms of Surya. After that, three more mystic words were created- Mahah, Jan and Tapah, each of the former word being grosser than the latter one. In the end, the word Satya was created, which was the grossest of all. These seven mystic words related with the Omkar illustrate the gross and the subtle forms of Vivasvan.