The temple is situated beside the N.H-14 about 32 kms north of Kollam and 5 kms south of Kayamkulam. ‘Oiman’ is an old form of Tamil word which means an architect and 'Chira' means a band or a narrow stretch of land. So it is assumed that at one time in remote antiquity ‘Oimanchira’ had been a place of Tamil architects. Later the word Oimanchira might have been shortened to form Oachira.

   The Absolute or Parabrahma is the main deity of the temple. Though we call it a temple there is neither a house of abode nor a temple building of any kind of its own. There are two huge spreading banyan trees surrounded by platform on which the rituals are performed by Non-Nampoothiris. Perhaps the Absolute might have dispensed with a proper shrine in order to enjoy himself in the sun and rain or of course, with the nature. One can see a number of bulls, small and big, in the courtyard which shed a new light on the belief that the Absolute deity is really the Lord Sri Parameswara. A special kind of black mud is given to the devotees as ‘Prasadom’. It is said that the special mud has got certain medicinal value.

   There is a story behind the origin of the temple which has been handed over from generation to generation. Vararuchi had twelve sons by a Chandala woman. They were known as “Parayipetta Panthirukulam”. The members of the family were: 1. Agnihothri 2. Rajakan 3. Uliyannoor Thatchan 4. Vallon 5. Vayilla Kunnilappan 6. Vaduthala Nair 7. Karackal Matha 8. Uppukuttan 9. Pananar 10. Naranathu Branthan 11. Akavoor Chathan 12. Pakkanar.

   Among them Akavoor Chathan was a faithful servant of the Nampoothiri of Akavoor Mana near Alwaye.

   The Nampoothiri was an expert and scholar in Vedic scriptures. One day Chathan asked his master, “How does the Parabrahma look like?” The Nampoothiri replied sarcastically, “It is just like the bull in our cattleshed”. This statement of the Nampoothiri was in fact, a turning point in Chathan’s life.

   Chathan didn’t think anything else other than the Parabrahma. He thought that he could find him if he had perseverance and steeled his heart to attain the goal. He became reluctant to wordly pleasures and led a pious life taking vows and rituals. In his search for Parabrahma he happened to come to Oachira, where he found a suitable place for prayer and worship. Because of his uninterrupted chanting and telling of beads he could reap the benefit of what he had sowed in his mind. The actual Parabrahma murthy appeared before him in the form of a bull. Chathan’s whole body was filled with piety. It was really the Parabrahma in disguise. Chathan became a pietist. The bull lingered here and there with Chathan and then disappeared.

   When the Nampoothiri heard about Chathan’s story and the Parabrahma revelation he realised that Chathan was more scholarly than he and bowed before Chathan in reverence and accepted him as his ‘Guru.’ Chathan till the end of his life remained at Oachira worshipping the almighty. Thus the soil of Oachira is blessed with the presence of the infinite God and people began to worship him with devotion.

   It is believed that in remote time the soldiers of Kayamkulam had been given training in warfare at the vast area near the temple, so that it was known as ‘Oachira Padanilam’. In memory of this practice in training, every year, in connection with the temple festival, trained men of different ‘Karas’ (Local people) assemble there and demonstrate a pseudo-fight known as ‘Oachira Kali.’

   On the first day of ‘Vrichikom’ (November) the temple premises are extensively illuminated with bright lights which symbolise the important main festival. It lasts for twelve days. On each day of the festival there will be a wide variety of entertainments including cultural programmes. Besides, a large number of devotees from different parts of Kerala come and settle in the huts put up for the purpose of meditation and prayer. They do so because of the favours they have received from the deity or for receiving favours. They live in the huts for 12 days chanting and singing hymns in praise of the Lord. The bulls at the temple which are considered as the divine vehicle of the deity, go round the huts and receive offerings from the devotees. It is a fact that the bulls at this temple are looked upon as sacred animals.

   The temple comes under the management of Parabrahma Temple Trust, which also runs a super speciality hospital at Oachira.