KYIV -- He is shaggy-haired and bearded, clad in a blue button-up shirt, dark trousers, and worn-in boots -- inconspicuous enough among the monks and their apprentices roaming the grounds of Kyiv's Svyato-Pokrovskyy Holosiivskyy Monastery.

But this blue-eyed man is different from all the others here.

He is 33-year-old Brazilian Rafael Lusvarghi, a former volunteer fighter and poster boy for Russia-backed separatists in eastern Ukraine before his arrest in Kyiv, conviction on terrorism charges, and 13-year prison sentence that would later be overturned.

Since his surprise release in December, after 14 months in jail, he has been secretly living within the red-brick walls of this monastery of the Ukrainian Orthodox Church of the Moscow Patriarchate, where he says he is learning the ascetic ways of a monk.

"When I was in prison I was reading books about the [Orthodox] religion, and I became a man of God," Lusvarghi, donning an apron, says in English after being approached outside the monastery's kitchen on April 29. "I pray every day."

Catch And Release

Lusvarghi's journey from Kalashnikov-firing pagan on the battlefields of eastern Ukraine to a monastic-in-training on the Orthodox Christian grounds of a monastery whose name translates as Holy Protection began on September 20, 2014, when he arrived via Russia in the area of the Donetsk and Luhansk regions controlled by Russia-backed separatists.

By mid-2015, the self-described former member of the French Foreign Legion with a history of scrapes with the law at home in Brazil and an avowed "great love for Russia" had fought in signal Ukrainian battles like the fights for the town of Debaltseve and Donetsk airport, while also serving as a military instructor and scout for separatist forces.

At the time, Lusvarghi -- a native Portuguese speaker who is fluent in Russian (he tried unsuccessfully to join the Russian Army in 2010) and has a strong grasp of English -- was not one to shy away from media, and his combat was regularly glorified by Russian and separatist propaganda.

In interviews with separatist propaganda outlets in Donetsk, he explained he came to Ukraine to fight "fascism." In an interview after he was injured in a firefight in summer 2015, he claimed also to have family roots in Eastern Europe. "When the war began, I was in Brazil, because I'm Brazilian. My family, we believe we're also Russian, because our ancestors -- though it was long ago -- were Belarusian," he said. "So it's a war for my motherland, too."

Such visibility helped him carry out another task at the time: recruiting foreign fighters in a yearslong conflict with many Russian combatants but also occasionally fighters from the United States, United Kingdom, Central Asia, or nearby Georgia.

Lusvarghi left eastern Ukraine via Russia and returned to Brazil in summer 2016, with the battle lines in Donbas mostly frozen but skirmishes creating casualties almost daily. Then he decided to return to Ukraine later in the year, following what he would soon discover was a false job offer from the Ukrainian Security Service. He was arrested upon arrival at Kyiv's Boryspil International Airport that October and soon put on trial.

In January 2017, Lusvarghi became the first non-Russian convicted for crimes related to the war when he was found guilty of creating a "terrorist organization" and "recruiting mercenaries for terrorists."

In an exclusive jailhouse interview with RFE/RL in March 2017, sporting a buzz cut and clean-shaven, the Brazilian said he hoped to be included in a future prisoner exchange with Russia-backed separatists, and that he was trying to overturn his conviction.

Much to Lusvarghi's surprise, in August, the Kyiv Court of Appeals quietly overturned the verdict, accepting the defense's arguments over jurisdiction and the prosecution's focus on his admission of guilt without considering all the evidence or his allegation of illegal force used against him, the Kharkiv Human Rights Protection Group reported at the time.

The appeals court ordered further investigation and a retrial, while extending Lusvarghi's detention.

Then in December, for reasons unknown to him, he was released from prison.

"Why I'm not in [prison], I don't know," he says, adding that the Ukrainian authorities gave neither him nor his lawyer, Valentin Rybin, a reason for his release. "I can't explain and I don't understand."

"It's chudo" -- a miracle -- he adds in Russian.

But it's a miracle with restrictions. Without his passport, currently held by Ukrainian authorities while they continue to investigate his case, he is stuck in the country he took up arms to fight.

Ukraine's Justice Ministry, Prosecutor-General's Office, and Security Service did not respond to requests to clarify the nature of his release and the status of the investigation.

Eat, Pray, Wait

It is thanks to a tip from a source with knowledge of his case who asked not to be identified, and confirmation from his lawyer, of his presence in Ukraine, that RFE/RL was able to track down Lusvarghi at the the Svyato-Pokrovskyy Holosiivskyy Monastery after two previous visits to another monastery nearby.

Tucked inside the forested Holosiiviskyy National Park just 10 kilometers from the center of the busy Ukrainian capital, life at the monastery is quiet and slow.

On the Sunday that RFE/RL visits, a few dozen visitors stroll its landscaped courtyard and a wedding party poses for photos. Around the corner from the courtyard, workers shuffle to and from a storeroom and a kitchen.

This is where we find Lusvarghi. With tousled hair and a bushy beard, he looks more like the fighter he was in 2015 than the clean-shaven prisoner he was in 2017.

When RFE/RL first approaches Lusvarghi and questions his identity, his eyes widen and he replies in Russian, "No, I'm not him," before backtracking and agreeing to an interview.

Against the backdrop of a golden-domed church and the recordings of singing monks wafting from surrounding speakers, Lusvarghi, who acknowledges he was not religious growing up and has been described as having a penchant for pagan symbols, says it was his idea to come here after his release in December. "I was already reading some books about [Orthodox] religion. I search a few monasteries here in Kyiv, and...," he explains, gesturing to the church.

A monk who identifies himself as Father Samson would later approach RFE/RL to say that the monks here believe Lusvarghi is innocent of the crimes Ukraine accuses him of committing, and that they agreed to provide him shelter.

Lusvarghi says he got a chilly reception from the Brazilian Embassy in Kyiv, which was unable to provide much help to him. Reached by phone, the embassy and the Brazilian Foreign Ministry decline to comment on Lusvarghi's situation.

Lusvarghi says he spends most of his days praying and working. That work can be general maintenance of the monastery grounds or food preparation. "Early in the morning, go to the service, pray. If you have time, you read some books," he says of his routine.

If work for the day is completed early, then in the evenings he says he's granted some "personal time." The rules for those who have made a commitment to become a monk are "very strict," he adds.

Partly because of that and partly because he tries to keep a low profile, Lusvarghi's communication with the outside world is minimal. He is not on social media, and he doesn't own a smartphone or a laptop computer. Instead, he carries an old-school, push-button Nokia phone. He says he is able to access the Internet using a monastery computer but rarely logs on, because it is frowned upon by his "spiritual fathers."

He says he is almost completely unaware of current events, including the status of the simmering, bloody war -- now in its fifth year -- in which he once fought.

"Can you tell me something about negotiations of prisoner exchanges?" he asks RFE/RL, referring to the swaps between Kyiv and Russia-backed separatists in Donetsk and Luhansk.

He says he had hoped to be included in the large prisoner exchange in December. He still hopes that he might be included in a future swap.

"Why I stayed back? Are there others who stayed back as well?" Lusvarghi asks. "I wanted to be exchanged. The fact that I stayed behind, it's against my will."

"I would like to return to my country. But, if it's the only option, I'm fine with returning to [separatist-held Donetsk]," he adds.

Frustration And Retrial

Lusvarghi, the father of two young boys -- 8 and 2 -- who is separated from his partner, explains that he has experienced "some depression" but mostly "frustration" over his current situation. Eating away at him is that he has been away from his family for a year and a half.

Asked whether he thinks about his days fighting in eastern Ukraine and has any remorse, he refuses to discuss that period.

Lusvarghi says his retrial is expected to begin on June 6.

While Lusvarghi worries about possibly being convicted again and handed a stiff prison sentence, history has shown there's a chance he could yet walk away from the ordeal.

He says he remains hopeful that he will be able to leave Ukraine someday. "Everything that's happened so far has been completely a surprise," he says. "Everything's possible."

With reporting by Levko Stek