Markandeya says- ‘During ancient times, the demons- Shumbh and Nishumbh had captured all the three worlds after defeating the deities. The deities went to Goddess Parvati and eulogised her by saying- ‘O goddess! You had promised us that you would come to our help at the time of our need. The time has arrived.’
As the deities were busy eulogising Goddess Parvati, she was preparing to go for her bath. She came near the deities and asked them as to who were they eulogising. Suddenly, a divine entity manifested from her body and answered on behalf of the deities- ‘These deities are eulogising me.’ This divine entity was none other than Goddess Shiva. As Shiva had manifested from the cell (Koshika) of Parvati’s body, she was also known as Kaushiki. Kaushiki possessed divine beauty. The demons, Chand and Mund happened to see her.
Both of them went to Shumbh and described to him about Kaushiki’s beauty. Shumbh wanted to marry her. He sent a messenger named Sugreev to Kaushiki to inform her about his intentions. Sugreev went to Kaushiki and said- ‘You are so beautiful. You are fit to marry a mighty demon king like Shumbh who rules over all the three worlds.’
The goddess laughed and said- ‘O messenger! I am ready to marry Shumbh or Nishumbh because I know they are very powerful but there is one problem. As I have taken a vow that I would marry only such a person who defeats me in a battle.’ The messenger replied- ‘O beautiful lady! How can you fight the mighty Shumbh who has defeated even the deities and who is the master of all the three worlds?’ Sugreev made persistent requests but the goddess refused to go along with him. She instructed him to inform Shumbh and Nishumbh about her vow.