Irina Cornici, 23, died from dehydration, exhaustion and suffocation during an ordeal that stunned Romania and prompted the Orthodox Church to promise reforms and psychological tests to screen potential clergy.
The former priest, Daniel Corogeanu, and four nuns were all convicted and sentenced in September but Corogeanu was freed pending an appeal, which he lost Tuesday. He was picked up by police in the remote northeast Wednesday and sent to jail.
Cornici, who had previously been treated for schizophrenia, had believed she heard the devil talking to her. Corogeanu and the four nuns decided to try an exorcism ritual in June 2005 using techniques that the Romanian Orthodox Church condemned as "abominable".
The church, which has benefited from a religious revival in recent years, defrocked Corogeanu and excommunicated the four nuns, who in September were handed five- and six-year jail terms.
When arrested Wednesday, Corogeanu said he would serve his term if that was God's will, the national news agency Rompres reported.
Corogeanu, a Romanian, dropped out halfway through training for the priesthood, but still served as a priest for the secluded Holy Trinity convent in northeast Romania because of a shortage of suitable candidates for convents and monasteries.