* Butler gets 18-month sentence but remains in Vatican house arrest
* Convicted of stealing sensitive documents * "I am not a thief," Gabriele tells court in final appeal
* Butler says acted out of "visceral" love for Church and pope
* Vatican spokesman evokes papal pardon
(Adds ex-butler spared jail, further detail, colour)
By Philip Pullella and Naomi O'Leary
VATICAN CITY, Oct 6 (Reuters) - A Vatican court convicted Pope Benedict's former butler of stealing sensitive documents and sentenced him to 18 months detention on Saturday, at the end of one of the most sensational trials in the recent history of the Holy See.
A Vatican spokesman said the pope, who reigns as a supreme monarch in the world's smallest city state, would "most likely" pardon Paolo Gabriele.
Until such time, he will serve his sentence under house arrest in his Vatican apartment and not go to an Italian jail as is foreseen by bilateral agreements due to the Vatican's lack of any such facility, his lawyer Cristiana Arru told Reuters.
She said the house arrest provision had been approved by the Vatican's promoter of justice, or prosecutor, after the verdict.
Gabriele, wearing a grey suit, remained impassive as the court delivered its verdict after two hours of closed-door deliberations that followed closing arguments by the prosecution and defence.
Gabriele had admitted being the source of leaks of highly sensitive papers, including letters to the pope that alleged corruption in the Vatican's business dealings and defended his actions in a final appeal before the court retired.
"What I feel most strongly inside myself is the conviction that I acted exclusively out of love, I would say a visceral love, for the Church of Christ and its visible representative," he said in a flat voice that betrayed no emotion.
"If I have to repeat it, I am not a thief," he added dryly.
The prosecution had asked for a three-year sentence while the defence asked the court to reduce the charges from aggravated theft to misappropriation, and for him to be freed.
The head of the three-judge panel, wearing a black robe with gold tassels, read the verdict with the opening words: "In the name of Holiness Pope Benedict XVI, gloriously reigning, the court, having invoked the Holy Trinity, has reached the following sentence."
The court also ordered Gabriele to pay the cost of the trial out of his own pocket but a Vatican spokesman was unable to quantify it.
BETRAYAL OF TRUST
The judge said he had given Gabriele a lighter sentence than sought by the prosecution because he had no previous criminal record and because he had "acknowledged that he betrayed the trust of the Holy Father".
The court was told how Gabriele, who served the pope his meals and helped him dress, photocopied sensitive documents under the nose of his immediate superiors in a small office adjacent to the papal living quarters in the Apostolic Palace.
He then hid more than 1,000 copies and original documents, including some the pope had marked "to be destroyed," among many thousands of other papers and old newspaper clippings in a huge armoire in the family apartment inside the Vatican walls.
The prosecution tried to portray Gabriele as a simple-minded man with "illusions of grandeur" who was easily influenced by others but said there was no proof that he had accomplices.
Arru told Reuters in an interview she did not plan to appeal because she felt the sentence was "a just one".
"He is a serene man. He placed himself before justice and is ready to accept any of the consequences," she said after visiting the Gabriele family in their apartment in the Vatican.
"He put his life in the hands of divine providence first and human justice second. He is a man who has no fear," she said, adding that the Vatican prosecutor had agreed that Gabriele would be permitted to take walks in the Vatican gardens under escort and receive relatives.
The trial, which started last Saturday, threw open the window on a betrayal of trust and sensitive secrets in the Vatican.
A former member of the small, select group known as "the papal family", Gabriele was one of fewer than 10 people who had a key to an elevator leading directly to the pope's apartments.
He said during the trial that from his perch as papal butler he was able to see how easily a powerful man could be manipulated by aides and kept in the dark about things he should have known.
In the course of the trial, intimate details emerged of the inner workings of an institution long renowned for its secrecy.
The documents Gabriele leaked constituted one of the biggest crises of Pope Benedict's papacy when they emerged in a muckraking expose by an Italian journalist earlier this year.
The case has been an embarrassment for the Vatican, coming at a time when it was keen to rid itself from the taint left by a series of scandals involving sexual abuse of minors by clerics around the world and mismanagement at its bank.
Gabriele told investigators before the trial began that he leaked the documents because he saw "evil and corruption everywhere in the Church" and that information was being hidden from the pope.
Earlier this week Gabriele accused the Holy See's police of mistreating him while in custody. Members of the force in turn depicted the butler as a man obsessed with the occult, Masonic lodges and secret services.
(Editing by Jon Boyle and Jon Hemming)
Keywords: POPE BUTLER/