The lingam here is believed to be from the Treta Yuga, the second age of Hinduism and is considered one of the oldest temples in Kerala where puja has not been broken since its inception.

[1] The demon Khara, on receiving the Shaiva Vidya Upadesha, (the knowledge of Shaivisim) from Malyavan went to the holy city of Chidambaram in present-day Tamil Nadu and did severe penances and meditation for the attainment of Moksha or liberation.

Pleased with his penance, Shiva appeared and granted all the boons he asked, and presented him with three great lingams, drawn out of Him.

He realized that it was Shiva's magic (maya) and when called unto, the heavens spoke thus, "I shall remain here giving Moksha (salvation) to whoever takes refuge in Me!".

Parashurama thought to himself that, Vyaghrapadapurma, the holiest place on Earth, could be a great refuge for the devoted who wish to attain liberation.

He taught the brahmin, the holy chants, mantras, procedures and shlokas necessary to perform puja to Shiva and initiated him as the chief priest of the temple.

It is believed that Shiva, also known here as Vyaghralayesha (the lord of Vyaghrapadapurma), gives His blessings to the devotees in three incarnations or avatars, in the morning as Dakshinamurthi, in the afternoon as Kiratamurthi, and as Shakti Panchakshari in the evening.

At that time the naivedyam, the food offered to the deity, was used to be placed in the western side of the Namaskara Mandapa hall.

The premises levelled with river sand is protected by compound walls with four gopurams or entrance towers on all the four sides.

[3][4] The Mukha Mandapa, the first pillared hall and chamber is built in shaped stone and single piece woods.

The garbhagriha or the sanctum sanctorum – the second chamber is built completely in stone including the roof in a square shape.

It signifies the six vikaras (impurities) which are Kama (lust), Krodha (anger), Lobha (power), Moha (attachment), Mada (ego) and Matsarya (envy).

This is well depicted in the famous Malayalam song, Naranayingane Janichu Bhoomiyil, written about the deity of this temple.