Aldo Bianchini, 46, who was born in Britain but lives in Italy, tore both his eyes out with his bare hands in front of a 300-strong congregation attending the church of St. Andrea's in Viareggio, on Sunday.
Emergency responders said Bianchini was calm and lucid when they arrived at the scene and told them a "voice told him" to rip his eyes out, according to news agency ANSA.
He was taken to the Versilia Hospital in Viareggio and his condition was described as very serious but not life threatening.
Emergency responders picked up his eyeballs from the floor of the church but they were unable to be replanted.
Gino Barbacci, the doctor who treated Bianchini, said it would have taken superhuman strength for a person to gouge their own eyes out and added he had never seen anything like it in 26 years of medical practice.