Pastor Manuel Rivera's voice echoes through the crowded courtyard in the notorious San Francisco Gotera prison in El Salvador, as hardened criminals weep and bow their heads in prayer. Brutal 'mara' street gangs and chronic poverty have made El Salvador one of the most murderous countries on the planet, but the growth of evangelical Christianity behind bars is giving gangsters a way to break the spiral of violence. Rivera, an ex-hitman from the powerful Barrio 18 gang, speaks to rows of men with spidery black tattoos on their arms, necks and faces, delivering a message of salvation: God had rescued them from violence. Returning to gang life would mean death. REUTERS/Jose Cabezas SEARCH "CABEZAS GOD" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY. Matching text: EL SALVADOR-VIOLENCE/

Edgar Matobato, a self-confessed former hitman, wipes his tears during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, answer questions during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, wipes his tears during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, bites his lips during a Reuters interview inside a safehouse in metro Manila, Philippines September 30, 2016. REUTERS/Romeo Ranoco TPX IMAGES OF THE DAY

Senator Alan Peter Cayetano (L) gestures while looking at Edgar Matobato, a self-confessed former hitman, during a Senate hearing on drug-related extrajudicial killings at Senate headquarters in Pasay city, Metro Manila, Philippines, September 22, 2016. REUTERS/Romeo Ranoco

Edgar Matobato (L), a self-confessed former hitman, chats with Senator and boxing champion Manny Pacquiao (R) and Senator Antonio Trillanes before the start of a hearing on drug-related extrajudicial killings at Senate headquarters in Pasay city, Metro Manila, Philippines, September 22, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures while his lawyer looks on during a Senate hearing on drug-related extrajudicial killings at Senate headquarters in Pasay city, Metro Manila, Philippines, September 22, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Senate hearing on drug-related extrajudicial killings at Senate headquarters in Pasay city, Metro Manila, Philippines, September 22, 2016. REUTERS/Romeo Ranoco

Edgar Matobato, a self-confessed former hitman, gestures during a Senate hearing on drug-related extrajudicial killings at Senate headquarters in Pasay city, Metro Manila, Philippines, September 22, 2016. REUTERS/Romeo Ranoco TPX IMAGES OF THE DAY

Edgar Matobato, a self-confessed former hitman, holds up a roll of tape, the type of which he claims he used on his victims, during a senate hearing on drug-related extra-judicial killings, in Pasay city, Metro Manila, Philippines, September 15, 2016. REUTERS/Ezra Acayan

Edgar Matobato, a self-confessed former hitman, attends a senate hearing on drug-related extrajudicial killings, in Pasay city, Metro Manila, Philippines, September 15, 2016. REUTERS/Ezra Acayan TPX IMAGES OF THE DAY

Edgar Matobato, a self-confessed former hitman, speaks during a senate hearing on drug-related extrajudicial killings, in Pasay city, Metro Manila, Philippines, September 15, 2016. REUTERS/Ezra Acayan

Julissa Aguilar (R), wife of late lawyer Eduardo Montes Manzano, leaves the building where her husband was murdered in Tegucigalpa, Honduras, September 16, 2015. Montes, who was the defender of Honduras' Congress vice president Lena Gutierrez, who is accused of defrauding the country's health ministry and falsification of documents, was stabbed several times by an alleged hitman at his office, local media reported. REUTERS/Jorge Cabrera

A forensic technician arranges the slain body of lawyer Eduardo Montes Manzano in the coroner truck in Tegucigalpa, Honduras, September 16, 2015. Montes, who was the defender of Honduras' Congress vice president Lena Gutierrez, who is accused of defrauding the country's health ministry and falsification of documents, was stabbed several times by an alleged hitman at his office, local media reported. REUTERS/Jorge Cabrera

REFILE - CORRECTING TYPOThe alleged killer of lawyer Eduardo Montes Manzano is surrounded by policemen after being detained in Tegucigalpa, Honduras, September 16, 2015. Montes, who was the defender of Honduras' Congress vice president Lena Gutierrez, who is accused of defrauding the country's health ministry and falsification of documents, was stabbed several times by an alleged hitman at his office, local media reported. REUTERS/Jorge Cabrera TPX IMAGES OF THE DAY

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF DEATH OR INJURYForensic technicians stand next to the body of slain lawyer Eduardo Montes Manzano as they prepare to take the body to a coroner truck in Tegucigalpa, Honduras, September 16, 2015. Montes, who was the defender of Honduras' Congress vice president Lena Gutierrez, who is accused of defrauding the country's health ministry and falsification of documents, was stabbed several times by an alleged hitman at his office, local media reported. REUTERS/Jorge Cabrera

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF DEATH OR INJURYForensic technicians carry the slain body of lawyer Eduardo Montes Manzano towards a coroner truck in Tegucigalpa, Honduras, September 16, 2015. Montes, who was the defender of Honduras' Congress vice president Lena Gutierrez, who is accused of defrauding the country's health ministry and falsification of documents, was stabbed several times by an alleged hitman at his office, local media reported. REUTERS/Jorge Cabrera

Cast member Zachary Quinto attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Zachary Quinto attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Director Alexsander Bach attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Zachary Quinto attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Director Alexsander Bach attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Director Alexsander Bach attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Director Alexsander Bach attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Director Alexsander Bach attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Director Alexsander Bach attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

(L-R) Cast members Rupert Friend, Hannah Ware and Zachary Quinto attend the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

(L-R) Cast members Hannah Ware and Rupert Friend attend the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

(L-R) Cast members Rupert Friend and Hannah Ware attend the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Hannah Ware attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend signs autographs as he attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Cast member Rupert Friend attends the premiere of "Hitman:Agent 47" in New York August 13, 2015. REUTERS/Andrew Kelly

Omar Hamid speaks with a Reuters correspondent before a book signing at a bookstore in Islamabad, Pakistan August 6, 2015. Hamid joined the Pakistani police vowing revenge after a hitman executed his father. Having left the force 12 years later, the Taliban murdered his replacement - the man who had arrested his father's killer and become his best friend. The two gritty, electrifying novels Hamid has published since are packed with versions of the underworld characters he met as he rose to become a top counter-terrorism cop in the bowels of one of the world's roughest cities, Karachi. REUTERS/Caren Firouz

Omar Hamid speaks with a Reuters correspondent before a book signing at a bookstore in Islamabad, Pakistan August 6, 2015. Hamid joined the Pakistani police vowing revenge after a hitman executed his father. Having left the force 12 years later, the Taliban murdered his replacement - the man who had arrested his father's killer and become his best friend. The two gritty, electrifying novels Hamid has published since are packed with versions of the underworld characters he met as he rose to become a top counter-terrorism cop in the bowels of one of the world's roughest cities, Karachi. REUTERS/Caren Firouz

Omar Hamid is reflected in a mirror as he speaks during a book signing at a bookstore in Islamabad, Pakistan August 6, 2015. Hamid joined the Pakistani police vowing revenge after a hitman executed his father. Having left the force 12 years later, the Taliban murdered his replacement - the man who had arrested his father's killer and become his best friend. The two gritty, electrifying novels Hamid has published since are packed with versions of the underworld characters he met as he rose to become a top counter-terrorism cop in the bowels of one of the world's roughest cities, Karachi. REUTERS/Caren Firouz

People pose for a photo while promoting the movie "Hitman: Agent 47" during the 2015 Comic-Con International Convention in San Diego, California July 9, 2015. REUTERS/Mario Anzuoni TPX IMAGES OF THE DAY

The "Hitman" video game is seen during game publisher Square Enix's media briefing before the opening day of the Electronic Entertainment Expo, or E3, in Los Angeles, California, United States, June 16, 2015. REUTERS/Lucy Nicholson

A woman touches a dog after it receives medical attention from paramedics next to a crime scene in Boca Del Monte, in the outskirts of Guatemala City, July 12, 2013. Paramedics say the dog was shot in the leg after biting a hitman who according to bystanders, shot and killed a woman in a street in Boca del Monte. Picture taken on July 12, 2013. REUTERS/Jorge Dan Lopez (GUATEMALA - Tags: CRIME LAW ANIMALS SOCIETY)

Police officers capture a suspected hit man after the murder of a bus driver in Zona 6 in Guatemala City April 22, 2013. A bus driver was shot to death in Zona 6 in Guatemala City for not paying extortion fees to a criminal gang, according to the police at the scene. REUTERS/Jorge Dan Lopez (GUATEMALA - Tags: CRIME LAW TPX IMAGES OF THE DAY)

ATTENTION EDITORS - VISUAL COVERAGE OF SCENES OF INJURY OR DEATH

A police officer kneels to take the fingerprints of a dead man in a neighborhood in San Salvador February 20, 2013. The man, a suspected member of the street gang Mara 18, was having drinks at a bar when a hitman arrived and shot him in the head, according to local media. Picture taken February 20, 2013. REUTERS/Ulises Rodriguez (EL SALVADOR - Tags: CRIME LAW CIVIL UNREST)

Spanish director Javier Rebollo (R) participates in a photocall alongside actors Jose Sacristan (L) and Valeria Alonso to promote El Muerto Y Ser Feliz (The Dead Man and being Happy), a road movie set in Argentina about a dying hitman, on the third day of the San Sebastian Film Festival September 23, 2012. The film is part of the festival's official section. REUTERS/Vincent West (SPAIN - Tags: ENTERTAINMENT SOCIETY)