After days of investigation, police said they believe the man, surnamed Kim, committed suicide without any assistance.
Kim is believed to have nailed his feet to the cross, tied his neck to it and stabbed himself in the side. He is then believed to have drilled holes in his hands and slipped them over nails on the cross, Gyeongbuk Provincial Police Agency officers said, describing the death under condition of anonymity because they weren't authorized to speak to the press.
Officials re-enacted some elements of the crucifixion and concluded that an adult male could perform the act on his own, the agency said.
The man was a devout Christian, and police speculated that his "deep religious faith" may have helped him endure "immense pain."
Police said they found the man's notes planning the crucifixion. Before his apparent suicide, Kim closed his bank account and canceled his mobile phone contract in apparent preparation to end his life, police said.
An autopsy on his body showed the man died of bleeding from the stab wound and suffocation, police said. Officers reached by The Associated Press said they had no information on when exactly the man put himself on the cross and how long he might have been there before dying.
Popular representations of the death of Jesus Christ depict him crucified between the crosses of two thieves, wearing a crown of thorns, a white cloth over his loins, with a wound on his side from a Roman soldier's spear.