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As the story goes in the Purunas, Lord Vishnu and Brahma compete to find the beginning or end of the Agni Linga to establish who is the superior deity. At the end of the competition Brahma and the witness Ketaki flower become ineligible for worship. My questions are as follows.
1) What or who exactly is the swaroopa of Agni Linga? Is it Lord Shiva or ParaBrahm? What does it Signify?
2) Is this story just a fabricated legend or is there any mention of this in the authentic Puranas?