There was a wealthy ruler of Panthalam named Rajashekhara but he had no children. He was a devotee of Lord Shiva and prayed to him for an offspring. Meanwhile, in the divine realms, the sister of Mahishasura, Mahishi secured a boon from Brahma that only the son of Shiva and Vishnu can kill her. She thought it’s impossible for a male and male to have a son. When the Devas approached Vishnu, he took the form of a beautiful female and tried to seduce Shiva but he as a Yogi, resisted her and gave her his energy. As a result, a child was born. Shiva tied a golden bell around his neck and sent him to Earth. Rajashekhara found this child and named him Manikanthan.
One day, Manikanthan went in a forest territory of Mahishi and both started fighting in which Mahishi was slayed. Then, Indra took a form of his tiger mount and became his vehicle. Indra wanted to build a temple for him and Manikanthan shot an arrow towards a hill. Vishwakarma built a temple on the hill and Lord Vishnu commanded Parshurama to disguise as an idol maker and make an idol of Manikanthan. Parshurama did it and installed the idol of Ayappa as Manikanthan on Makar Sankranti. Shabarimala is where the devotee of Rama, Shabari used to live and this is where the temple of Ayappa is.