Mr Naik was offering his genitals to the Hindu god Shiva
A horrified priest found Natabar Naik unconscious on a temple floor.
He and a gardener said that they saw him praying in the building the night before But the 40-year-old stayed on to worship when it was locked up for the night.
Drops of blood found by the priest the following afternoon led to Mr Naik in Alasu, eastern India.
He is recovering in hospital while cops wait to talk to him to unravel the gory drama.
But local sources believe devout Mr Naik castrated himself and offered the testicles to Nandi, the guardian bull of Hindu god Shiva.
He had been suffering severe epilepsy for years and was fed up with the failure of various treatments to curb it.
Mr Naik castrated himself as a last ditch attempt to cure his epilepsy
And sacrificing his testes was apparently a desperate last-ditch bid to get rid of the neurological disorder.
A blood-drenched knife was recovered by police from the temple.
There has been no official statement from medics about Mr Naik.
But news sources said his condition deteriorated after he was taken to one hospital and was transferred to specialist MKCG Hospital in Berhampur.
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Inspector Chitta Ranjan Behera told the Deccan Chronicle: “We are waiting for Natabar Naik's full recovery.
“As of now, we don't know much about the incident.
Mr Naik is now recovering in hospital
“We can take statements only after he recuperates from the injury.”
Worshippers in the temple where he was found are meanwhile performing purifying rituals so they can use the place again.
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