The temple's antiquity is well-established in ancient Sangam literature (Puranaanooru) and the hymns of the great Alwar saint, Nammalvar. In 1510 CE, the great saint Chaitanya Mahaprabhu visited this temple and miraculously discovered the lost, ancient manuscript of the 'Brahma Samhita' here, adding immense pan-Indian Vaishnava significance to the site.

Kadu-Sarkara Yogam and the Three Doors

The temple is a masterpiece of traditional Kerala-style architecture with intricately carved wooden pillars, sloping roofs, and exquisite ancient mural paintings. The most astonishing feature is the main deity. The massive 22-foot idol is NOT made of stone or metal. It is crafted using Kadu-Sarkara Yogam—an ancient, highly complex Ayurvedic mixture of 108 different herbs, mustard, jaggery, and river sand. Due to the idol's immense size, devotees must view the Lord in three segments through three separate wooden doors: the face (first door), the torso (second door), and the lotus feet (third door).

According to the puranas, Lord Vishnu fought a fierce battle with the demon Kesi. After defeating him, the Lord used His massive serpent bed (Adishesha) to bind the demon and lay over him to prevent his escape. Kesi's demonic wife invoked the rivers Thamirabarani and Kothai to flood the area and drown the Lord. However, Bhoomi Devi (Mother Earth) elevated the land where the Lord rested. The defeated rivers altered their course, peacefully encircling the temple like a garland.

Worship strictly follows Kerala Tantric traditions rather than standard Tamil Agamas. Male devotees must adhere to a strict dress code: shirts and inner garments must be removed before entering the inner prakaram (wearing only a dhoti/mundu). The poojas are deeply steeped in ancient rituals, and the temple actively maintains a highly serene, uncommercialized atmosphere.

The historic Battle of Colachel (1741). Local history dictates that the Travancore King Marthanda Varma laid his famous sword at the lotus feet of Adikesava Perumal, seeking divine intervention before facing the technologically superior Dutch East India Company. Miraculously, the Travancore army crushed the Dutch naval forces. The King firmly believed that Adikesava Perumal Himself rode unseen into battle to secure the victory for the native kingdom, and subsequently dedicated massive wealth and land to the temple in gratitude.

The major festivals are the Panguni Brahmostavam (March-April) and the Aipasi Brahmotsavam (October-November). Vaikuntha Ekadasi is also celebrated with tremendous grandeur, drawing thousands of pilgrims from both Tamil Nadu and Kerala.